Four counties · different math

Statewide averages hide the island you are actually buying.

A cesspool quote, electric bill, insurance deductible, or freight invoice is not a statewide number. It belongs to one county system, one utility, and one set of site conditions. Start with the island, then open the calculator.

Reviewed September 3, 2026

Hawaiʻi State Capitol in Honolulu — Hawaiʻi State Capitol, Honolulu · CC BY 2.0 · Cliff. Representative government-records context—not a specific parcel.

Start here. Use these county pages to see which cost lines move first, which official records to open, and which Hawaiʻi Home Wise tools belong with that island—without treating any page as a price, appraisal, or clearance.

Comparable facts

Island cost-line comparison

A statewide average hides the utility, wastewater, hazard, and county-record stack that actually belongs to the island.

Hawaiʻi IslandCatchment or county water, cesspools, lava-zone records, rock excavation, and a long last mile from Hilo or Kawaihae. USGS lava-flow hazard information

OʻahuMonthly carrying cost: Honolulu tax treatment, AOAO deductibles, leasehold, commute, and DPP records. Honolulu permit status search

Maui CountyWater-meter reality, MAPPS permits, insurance indications, and Molokaʻi or Lānaʻi freight—not only South Maui prices. Maui MAPPS permit search

KauaʻiKIUC electricity, a smaller contractor pool, county water and building records, and hurricane cash need. Kauaʻi Island Utility Cooperative

Choose the county

What changes first on each island.

County of Hawaiʻi

Hawaiʻi Island

Do not treat a Hilo municipal-water house like a Puna catchment lot, and do not treat a lava-zone map as an insurance or lender decision. Pull County of Hawaiʻi records, then replace every calculator default with that property.

Open Hawaiʻi Island guide →

City and County of Honolulu

Oʻahu

Price the full Honolulu County carrying cost—tax treatment, insurance, association layers, commute, and cash to close—then open DPP and Board of Water Supply records before treating a listing as complete.

Open Oʻahu guide →

County of Maui

Maui

Confirm whether a Maui County property has an actual water meter, current insurance indications, and MAPPS or paper permit history before treating a resort-area price as a complete ownership number.

Open Maui guide →

County of Kauaʻi

Kauaʻi

Use KIUC for electricity research, County of Kauaʻi Building Division and Planning GIS for records, and written freight and contractor schedules before importing an Oʻahu or statewide budget.

Open Kauaʻi guide →

Local words

Terms that show up in Hawaiʻi listings.

TMK, leasehold, AOAO, cesspool versus septic, hurricane deductibles, and lava zones are not mainland glossary extras. They change cash need.

TermTMKCopy the TMK exactly as the county shows it, confirm it matches the property you intend to buy, and still run title, permit, and physical-condition research separately.TermLeasehold vs fee simpleRead the tenure on the deed and condominium documents, then price remaining term, lease rent, renegotiation, and lender treatment before using price per square foot.TermHurricane deductibleRead the deductible as a dollar cash-need problem: dwelling limit × deductible percent, minus any savings you would actually use. Then confirm named-storm definitions and exclusions with a licensed insurer.TermLava zonesLocate the property independently, read the current USGS hazard information, write down the source and date, and ask an insurer and lender what they require. Do not skip that step because a listing looks far from a vent.TermAOAORequest the current budget, reserve study, master-policy declarations, minutes, house rules, and fee schedule. Then model deductible and assessment exposure before ranking buildings by asking price.TermCesspool vs septicIdentify the actual system from records and a qualified inspection, then use Hawaiʻi Department of Health wastewater pages for current conversion and support information. Do not price the job from a statewide average.