The CRE Due Diligence Checklist: What to Review Before You Close

What Is CRE Due Diligence

Commercial real estate due diligence is the structured investigation a buyer conducts between an executed LOI and closing. It is your contractual window to verify every material claim made in the offering memorandum, confirm that the financial model holds up against actual operating history, and surface risks that were not disclosed or not obvious at first look.

A proper CRE due diligence checklist covers five distinct categories: financial, physical, legal and title, environmental, and market. Each category can independently kill a deal or trigger a price renegotiation. Treat them as parallel workstreams, not a sequential to-do list.

The goal is not to find a reason to walk. The goal is to close with confidence, knowing exactly what you are buying, what risks you are accepting, and what leverage you have at the table. Teams that approach commercial real estate due diligence systematically close better deals than teams that work from memory and instinct.

Financial Due Diligence

Financial due diligence verifies that the income and expense history the seller has presented reflects actual operating performance. The offering memorandum is a marketing document. The T12 and rent roll are closer to ground truth, but even those require cross-referencing. Pull the bank statements, tax returns, and utility bills. Numbers should reconcile across all three sources.

For a deeper look at how to read a trailing twelve-month statement, see our guide to what a T12 is and how to use it in underwriting. For the full underwriting framework, including how to build from T12 to DCF, read how to underwrite multifamily real estate.

• T12 review: verify trailing twelve months of income and expenses line by line. Reconcile against bank statements and tax returns. Flag any one-time income items — insurance proceeds, back-rent payments — that inflate the baseline NOI.
• Rent roll analysis: confirm every unit or tenant, current in-place rent, lease start and expiration, any concessions, and security deposits held. Check for vacancy timing, short-term leases expiring at close, or month-to-month tenants who could vacate immediately.
• Lease abstracts: review every executed lease for rent escalation clauses, renewal options, termination rights, co-tenancy provisions, exclusivity clauses, and landlord work obligations. In retail and office, these lease terms can swing value dramatically.
• Capital expenditure history: request a three-to-five year capex ledger. Understand what has been spent, what is deferred, and what the seller characterizes as a capital improvement versus a repair expense.
• Utility bills: verify utility costs against the T12, especially for properties with master-metered or owner-paid utilities. Confirm which utilities are tenant-paid versus owner-paid and whether the current lease structure supports the underwritten expense load.
• Property tax history: pull the tax bills for the past three years. Confirm the current assessed value and whether a sale will trigger a reassessment. In states with reassessment on transfer, the pro forma tax load could be materially higher than the in-place T12 figure.
• Insurance history: review three years of insurance premiums and claims history. Large claims can flag deferred maintenance or recurring physical issues. Premium increases signal elevated risk from the insurer's perspective.
• Accounts receivable aging: for any property with commercial tenants, request the AR aging report. Tenants with 60-plus day balances are collection risks. In multifamily, review the delinquency report and current eviction activity.

Physical Due Diligence

The physical condition of the asset directly affects your near-term capex requirements and your ability to execute the business plan. A property that looks well-maintained at a broker tour can have $2 million in deferred maintenance that only a qualified inspector surfaces. Do not skip or compress this workstream.

Commission a Property Condition Assessment from an independent engineering firm, not from a vendor referred by the seller. The PCA is your foundation. Supplement it with specialized inspections where warranted by the property type, age, or geography.

• Property Condition Assessment (PCA/PCR): a full PCA from a qualified third-party engineering firm is non-negotiable. Review the immediate repair table and the 10-year replacement reserve schedule. Reconcile PCA findings against the seller's disclosed capex history and flag any discrepancies.
• Roof inspection: roofs are among the most common sources of deferred maintenance surprises. Commission a standalone roof inspection with a remaining useful life estimate and repair/replacement cost. Flat roofs and built-up membrane systems require particular attention.
• HVAC systems: confirm the age, make, model, and service history of all HVAC units. Central plant systems in office or retail carry higher replacement costs. Determine whether systems are covered under service contracts and whether warranties transfer to the new owner.
• Plumbing and electrical: inspect all plumbing for cast iron versus PVC, evidence of past leaks, and water pressure. For electrical, confirm panel capacity, breaker age, and whether the building has been updated to modern code. Older properties may carry knob-and-tube or aluminum wiring that insurance carriers will flag.
• ADA compliance: confirm compliance with the Americans with Disabilities Act for parking, building access, restrooms, and common areas. Non-compliance can expose a new owner to liability and retrofit costs that were not underwritten.
• Deferred maintenance estimate: build your own independent deferred maintenance schedule from PCA findings, roof report, and inspector notes. This becomes the basis for price renegotiation if the seller's disclosed condition does not match third-party findings.

Legal and Title

Legal due diligence protects your ownership interest and your ability to operate and exit the property as planned. Title issues, undisclosed easements, and zoning non-conformities can take months to resolve and can kill a deal or severely constrain the business plan. Start title work immediately after LOI execution.

• Title search: order a preliminary title report from a reputable title company. Review all exceptions carefully. Pay attention to Schedule B-II exceptions, which represent matters that will survive closing unless cured. Negotiate for title insurance covering both your lender and your equity position.
• CC&Rs (Covenants, Conditions, and Restrictions): review all recorded CC&Rs that run with the land. These can restrict use, appearance, tenant mix, and signage in ways that materially affect the business plan. CC&Rs are permanent and cannot be easily modified.
• Easements: identify all recorded easements on the property, including access easements, utility easements, drainage easements, and view easements. Easements can limit development potential, parking configurations, and site improvements.
• Zoning confirmation: confirm current zoning designation, permitted uses, FAR, setback requirements, and parking ratios. If the property is legally non-conforming, understand what triggers the non-conformity and whether a renovation or change of use would require compliance with current code.
• Pending litigation: request seller disclosure of all pending or threatened litigation related to the property, including tenant disputes, neighbor disputes, personal injury claims, and construction defect claims. Order a lien search to surface any undisclosed claims.
• Environmental liens: confirm no environmental liens or deed restrictions exist that would survive closing. These can arise from prior contamination, regulatory orders, or voluntary cleanup agreements with the EPA or a state agency.
• Survey review: obtain an ALTA/NSPS survey and review for encroachments, boundary discrepancies, and anything that conflicts with the title report. The survey and title policy must be cross-referenced before closing.

Environmental

Environmental issues are among the most expensive and time-consuming problems a buyer can inherit. Unlike a leaky roof or an aging HVAC, contaminated soil or groundwater can cost millions to remediate and can trigger federal or state regulatory involvement that persists for years. Environmental due diligence is not optional on any commercial acquisition.

• Phase I Environmental Site Assessment: a Phase I ESA is a non-invasive desktop and site review conducted by a qualified environmental professional. It reviews regulatory databases, aerial photographs, historical uses, and site conditions for recognized environmental conditions (RECs). A Phase I is standard on every acquisition, and most lenders require one as a condition of financing.
• Phase II ESA (if warranted): if the Phase I identifies RECs, a Phase II is required. Phase II involves physical sampling of soil, groundwater, and building materials. Do not skip a Phase II if it is recommended. The cost of the study (typically $5,000 to $30,000) is trivial relative to the liability you may be accepting without it.
• Underground storage tanks (USTs): former gas stations, industrial sites, and older commercial properties often have USTs that were not properly decommissioned. Confirm tank status through records and Phase I findings. Active or abandoned USTs represent significant liability.
• Asbestos and lead-based paint: pre-1980 buildings frequently contain asbestos-containing materials and lead-based paint. If the Phase I or PCA flags these, order an asbestos survey and lead survey. Quantify the abatement cost and factor it into your pricing or closing credits.
• Flood zone classification: confirm the FEMA flood zone designation via the Flood Insurance Rate Map. Properties in Special Flood Hazard Areas (Zone A or AE) require flood insurance that can add significantly to annual operating costs. Confirm whether the designation has changed recently or whether an active LOMA or LOMR is in process.

Market Due Diligence

Market due diligence validates the assumptions in your underwriting model against actual market conditions. Your projected rent growth, stabilized occupancy, and exit cap rate are all market-driven assumptions. If the data does not support them, the model is fiction.

Conduct market diligence independently, using your own sources and broker conversations rather than relying solely on data the seller has provided. Sellers curate supporting market data to validate their asking price. You need an unfiltered view.

• Rent comps (past 12 months): pull comparable lease transactions from the past 12 months within a competitive radius. For multifamily, this means unit-level comparables by bed and bath configuration. For commercial, gross versus NNN rents and tenant improvement allowances matter. Confirm your projected rents are supported by actual closed transactions, not asking rents.
• Sales comps: pull comparable sales over the past 12 to 24 months to validate your exit cap rate assumption. Focus on transactions of similar asset quality, vintage, and tenancy. Understand the supply-demand dynamics that drove pricing in each comp.
• Vacancy trends: review submarket vacancy data from the past eight quarters. Is vacancy tightening or rising? A market with rising vacancy undermines lease-up assumptions and exit cap rate projections. Confirm occupancy at competing properties, not just submarket averages.
• Supply pipeline (1-3 mile radius): identify all projects currently under construction or in entitlement within your competitive trade area. New supply can compress rents and extend lease-up periods. For multifamily, check municipal permitting databases and CoStar or Yardi for planned deliveries over your projected hold period.
• Job market and employment base: for any income-producing property, the tenant base ultimately depends on employment. Review major employer concentrations, recent layoffs or expansions, and the diversification of the local economy. Single-employer markets carry concentration risk that broad submarket averages can mask.
• Population and demographic trends: review five-year population growth projections, household formation trends, and income growth for the submarket. Markets with sustained in-migration and household formation provide a structural tailwind for rent growth and occupancy.

Timeline and Process

A well-run CRE due diligence process does not wait until all documents are in hand before starting. You open workstreams in parallel on day one and work toward a gated review at day 30, where you make a go/no-go decision on proceeding to closing. The second 30 days is for resolving open items, finalizing lender requirements, and completing closing deliverables.

Teams using AcquiOS's Due Diligence PM feature can set up the full Gantt timeline, assign workstreams to team members, and track open items against the closing schedule automatically. The platform's document analysis capability also compresses the financial workstream by extracting T12 and rent roll data in minutes rather than hours, so the team can focus on interpretation instead of data entry.

Days 1-7: Open All Workstreams

• Execute NDA and request full diligence package from seller
• Order title search, ALTA survey, and Phase I ESA
• Engage PCA engineering firm and schedule site inspection
• Request T12, rent roll, all executed leases, and trailing capex ledger
• Begin financial model build from T12 and rent roll data
• Start market comps pull for rent and sales

Days 8-21: Deep Review

• Complete T12 reconciliation and identify any income normalization adjustments
• Abstract all leases; flag non-standard provisions for legal review
• Receive and review PCA; order any follow-on specialty inspections
• Review preliminary title report; submit title objections to seller
• Complete rent and sales comp analysis; update model assumptions
• Review Phase I; determine whether Phase II is warranted

Days 22-45: Issue Identification and Renegotiation

• Compile all findings into a written due diligence summary
• Quantify the financial impact of material findings (deferred maintenance, lease issues, tax reassessment)
• Present findings to seller; negotiate price adjustment or closing credits where warranted
• Receive lender appraisal and environmental report; address any lender objections
• Resolve outstanding title exceptions

Days 46-60: Close-Out and Closing Prep

• Confirm all open diligence items are resolved or accepted
• Finalize loan documents and coordinate with title company
• Complete final walkthrough and confirm property condition
• Review and approve closing statement prorations
• Fund and close

Frequently Asked Questions

How long does CRE due diligence take?

The standard CRE due diligence period is 30 to 90 days, depending on property complexity, asset type, and financing requirements. Smaller deals with clean documentation can close in 30 to 45 days. Larger transactions involving complex leases, environmental findings, or lender requirements typically require 60 to 90 days. Negotiate the longest reasonable period upfront. You can always close early, but extensions require seller agreement and sometimes cost money.

What is the most important part of due diligence?

There is no single most important category. Financial, physical, legal, and environmental findings all have the potential to kill a deal or significantly reset the price. That said, financial due diligence tends to surface issues earliest because the T12 and rent roll are typically available in week one. Physical and environmental issues take longer to surface because they depend on third-party reports. The most common week-one deal-killers are inflated NOI, occupancy misrepresentation, and undisclosed tenant credit issues.

What is a Phase I ESA?

A Phase I Environmental Site Assessment is a non-invasive environmental review conducted by a qualified environmental professional. It does not involve any soil or groundwater sampling. The Phase I reviews regulatory databases, historical aerial photographs, prior site uses, and physical site conditions to identify recognized environmental conditions (RECs) that could indicate contamination. All commercial acquisitions require a Phase I, and most lenders require one as a condition of financing. If the Phase I identifies RECs, a Phase II with invasive sampling is typically necessary before closing.

Can AI help with CRE due diligence?

AI can significantly accelerate the financial and document review workstreams. AcquiOS's document analysis capabilities extract and reconcile T12 data, rent roll detail, and lease abstracts in minutes rather than hours, reducing manual entry errors and surfacing inconsistencies faster. The Due Diligence PM feature provides Gantt-based project tracking, gate reviews, and a risk register so teams can manage the full 60-day process without items falling through the cracks. AI does not replace legal, engineering, or environmental specialists, but it compresses the time required for the financial workstream substantially and gives teams better visibility into what is still open.