Start with the tanks
Every underground storage tank (UST) system in California is permitted and inspected through the local Certified Unified Program Agency (CUPA), under rules set by the State Water Resources Control Board. Under a 2014 law, single-walled tanks and piping without secondary containment and continuous leak monitoring had to be permanently closed — removed or closed in place with agency approval — by December 31, 2025. Enforcement began January 1, 2026, with penalties that can run from hundreds to thousands of dollars per day per tank. Before anything else, get from the seller:
- The current UST operating permit from the CUPA and the last several inspection reports.
- Tank and piping construction (double-walled with interstitial monitoring is what you want), installation dates, and the monitoring system certification.
- Any open or closed leak cases with the regional water board, and whether the site has ever claimed on the state's UST Cleanup Fund.
- Vapor-recovery equipment status with the local air district (California's enhanced vapor recovery requirements apply to dispensers and nozzles) and any pending upgrade orders.
If the real estate is part of the purchase, a Phase I environmental site assessment is the minimum, and a Phase II with soil and groundwater sampling is common at fuel sites. Contamination discovered after you own the land is yours to clean up; lenders know this and will insist on the reports.
The fuel supply agreement
Most stations sell fuel under a branded supply agreement with a major brand or its distributor (a “jobber”). The contract sets the term (often 10–15 years from signing), minimum gallons, image and canopy standards you must maintain, and what happens on a sale — typically the supplier must approve the buyer, and the agreement is assigned with its remaining term. An unbranded station buys on the open rack and keeps more flexibility but has less brand traffic and no supplier support. Read the agreement itself, not the seller's summary, with an attorney who has seen them; the exit terms and minimum-volume penalties matter most.
Where the profit actually is
Fuel margins are thin and volatile — a handful of cents per gallon after credit card fees on many days. The reliable earnings usually come from inside sales (convenience store, tobacco, beer and wine, lottery, food service) and from a car wash or service bays if the site has them. So the diligence looks like a convenience-store purchase layered on top of the tank work:
- Gallons by month from supplier statements and dispenser totalizers, and the pool margin per gallon.
- Inside sales by category from the POS, reconciled to sales-tax returns filed with the CDTFA.
- Lottery commissions from California Lottery statements and tobacco sales from supplier invoices — both are licensed and audited, so the records exist.
- Credit card processing statements, because card fees on fuel are a real cost the P&L sometimes hides.
- Three years of tax returns and bank statements, as with any business.
Licenses: what a buyer must reapply for
| License / permit | Transfers? | Notes |
|---|---|---|
| UST operating permit (CUPA) | Reissued to the new owner/operator | Notify the CUPA; a designated UST operator and monitoring certification are required |
| Fuel supply agreement | Assigned with supplier approval | Buyer typically vetted by the brand or jobber |
| Seller's permit (sales tax) | No — apply in your name | Request a CDTFA tax clearance so unpaid sales tax does not follow you |
| Cigarette & tobacco retailer license (CDTFA) | No — apply in your name | Plus any local tobacco retail license |
| California Lottery retailer contract | No — new application | Lottery approves the new retailer; plan for the gap |
| ABC license (Type 20 beer & wine or Type 21 general, off-sale) | Person-to-person transfer | 30-day posting, ABC review, consideration through escrow; see the liquor store guide |
| Weights & measures device registration (county sealer) | New owner registers | Dispensers are inspected and sealed by the county |
| Air district permit (vapor recovery), hazardous materials business plan | Updated to new operator | Both through the CUPA / air district |
Every California business sale also carries a bulk-sale notice, the CDTFA clearance, and an EDD clearance if there are employees. Your escrow company should be one that handles fuel sites regularly; the license timing is the part that most often delays closing.
Business only or with the real estate
Stations are sold both ways. With the land, you take the environmental liability and a larger loan (commonly SBA 504 or conventional commercial financing for the property, SBA 7(a) or seller financing for the business), but you control the site and the supply relationship. Business-only deals rest on the lease — term, options, assignment, and whether the landlord or the tenant owns the tanks and is responsible for them, which the lease must say clearly.
Red flags
- Single-walled tanks or piping, an expired or conditional UST permit, or an open leak case.
- A supply agreement the seller cannot produce, or one with few years left and heavy minimum-gallon penalties.
- Inside sales in a spreadsheet only, or lottery and tobacco figures that do not match the agency statements.
- Missing vapor-recovery upgrades or air-district notices.
- Land offered without a Phase I — or a seller who resists a Phase II at a fuel site.
Where to look
Gas stations on Nalren appear under Business listings and, when the land is included, under Commercial. Browse businesses for sale and commercial property for sale across California; inventory is limited, so watch the listings in the cities you want.