Key takeaways
- Due diligence answers one question: is the property what you think it is, at the price you agreed to?
- Put the riskiest items first. Zoning, environmental, and title problems can kill a deal outright.
- In Florida, check flood zone, insurance cost, and the post-sale property tax reassessment early.
The checklist
| Area | What to get or check | Why it matters |
|---|---|---|
| Title | Title commitment, recorded documents, liens, easements | Defects can block financing or limit use |
| Survey | ALTA/NSPS survey | Boundaries, encroachments, easements, flood zone, access |
| Zoning and land use | Zoning designation, permitted uses, zoning verification letter, open code cases | Confirms the intended use is allowed and whether the property is nonconforming |
| Environmental | Phase I Environmental Site Assessment (ASTM E1527-21); Phase II if recommended | Lender requirement; supports defenses under federal environmental law |
| Physical | Property condition assessment: roof, structure, HVAC, plumbing, electrical, paving, ADA | Capital needs drive the real price |
| Leases | Every lease and amendment, tenant estoppels, SNDAs | Confirms the income is what the rent roll says |
| Financials | T-12, prior years, bank deposits, tax bills, utility bills, service contracts | Rebuild NOI from documents |
| Flood | FEMA flood zone and elevation information | Insurance cost and lender requirements |
| Insurance | Quotes for property, wind, flood, and liability | Florida insurance costs can move NOI materially |
| Property tax | Estimate the post-sale assessment | Florida's non-homestead assessment cap resets at sale |
| Utilities and access | Water, sewer, power capacity, curb cuts, driveway permits | Use limits and development cost |
Order matters
Start with the items that can end the deal and cost little to check: zoning, title, flood zone, and a read of the leases. Then order the survey, Phase I, and property condition report. Spending on reports before knowing the use is allowed wastes money and days on the clock.
About the Phase I ESA
A Phase I Environmental Site Assessment reviews records, site history, and site conditions for recognized environmental conditions. EPA recognizes ASTM E1527-21 as satisfying its All Appropriate Inquiries rule, which matters for certain landowner liability protections under federal law. Most commercial lenders require one.
Common questions
How long is due diligence on a commercial property?
It's set by contract, commonly 30 to 90 days, depending on property type, financing, and the reports needed.
Do I need a Phase I environmental report?
Most commercial lenders require one, and it supports certain defenses under federal environmental law. It's a standard part of commercial due diligence.
What is a zoning verification letter?
A letter from the local government confirming a property's zoning designation and, often, whether the current use is permitted or legally nonconforming.
Sources
- Federal Register, Standards and Practices for All Appropriate Inquiries (Dec. 15, 2022), recognizing ASTM E1527-21
- FEMA Flood Map Service Center
- Section 193.1555, Florida Statutes
Sources retrieved October 2, 2026.
General information, not legal, tax, accounting, or investment advice. This is a general checklist. Your attorney, lender, and consultants will tailor due diligence to the property. Examples marked illustrative use hypothetical numbers.