Land Due-Diligence Checklist
Hawai'i Island · Reviewed July 2026
Keala M. Wall · RS-82797
Take this to every parcel you're serious about. Write the answer on the line under each item — if you can't answer one, that's the next question for your agent, not a reason to skip it.
Parcel
TMK (Tax Map Key)The parcel's legal identifier. Everything else is looked up from this — get it before anything else. Acreage & zoning districtAg zones set the minimum lot size: A-1a is 1 acre, A-20a is 20, A-200a is 200. The zone decides what you may build and whether you can ever subdivide. The Rock
USGS lava hazard zone (1–9)Zone drives insurance, financing, and resale more than any other single factor. Confirm from the county GIS or the TMK record — never from a verbal description. Insurability at that zoneIn Zones 1–2 the state fund (HPIA) is often the only option, and its dwelling limit caps at $450,000. Get a real quote before you remove contingencies. Access
Recorded legal accessA road you can drive is not necessarily a road you may legally use. Look for a recorded ingress/egress easement on the title. Road maintenance & conditionWho maintains it, is there a road association fee, and is it passable in heavy rain? Water
County meter, catchment, well — or nothingA county line running past the lot is not the same as an active, metered connection. Verify with the Department of Water Supply. If catchment: tank, diverter, filtrationTank material (never rusted steel), first-flush diverter, and filtration. Plan for UV or reverse-osmosis for drinking water. If a well is the plan: is it permitted?Wells need State DLNR Commission on Water Resource Management approval. It isn't guaranteed and can take many months — never assume you can just drill. Power
Utility service to the lot, or off-grid onlyIf it's off-grid, price the full system: solar array, battery bank, inverter, and a backup generator. Current solar incentivesThe federal residential credit ended for systems installed after 31 Dec 2025. Hawai'i's state credit (35%, capped at $5,000) still applies as of 2026 — confirm with your tax professional. Waste
Septic, cesspool, or nothing yetIf there's a cesspool you inherit the obligation to convert it — every cesspool in Hawai'i must be upgraded or converted by 1 January 2050 under Act 125. Conversion budgetBudget $30,000–$50,000 or more, sooner rather than later near sensitive coastline. Perc test for new constructionA licensed engineer's percolation test is required before the county will approve a septic system. Flags That Change the Deal
CPR (Condominium Property Regime) lot?CPR parcels carry their own financing and building limits — tell your lender early. State Conservation District?Building needs BLNR approval, and that process is measured in many months. Ag exemption status & obligationsThe lower ag tax rate requires demonstrated active farming. Passive ownership can be reassessed — sometimes retroactively. Before you write the offer: the three that most often derail a Big Island land purchase are legal access, water, and septic feasibility. If any of those three is still a question mark, it belongs in your contingencies.
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