Why Fullerton Is One of the Best Cities in Orange County for ADU Investment Properties
If you're looking for an ADU investment property in Orange County, Fullerton should be at the top of your list. Here's why.
Lower Entry Price Than Most of OC
Fullerton has one of the lowest entry points for single-family homes in a desirable Orange County city. While the OC-wide median sits above $1.2 million, you can still find single-family homes in Fullerton starting in the high $800Ks to low $900Ks — especially in areas south of Commonwealth and near downtown.
That lower entry price matters because it means your all-in cost (purchase + ADU construction) stays manageable, and your numbers actually work from day one. In cities like Irvine or Huntington Beach, you're spending so much on the main home that the ADU income barely moves the needle. In Fullerton, the math is different — the ADU rental income can make a real impact on your monthly cash flow.
Corner Lots Create the Best ADU Opportunities
This is something most investors overlook, and it's one of the biggest advantages Fullerton offers: larger corner lots.
Many of Fullerton's older neighborhoods — particularly near downtown, along Harbor Blvd, and in the areas around Raymond Ave and Valencia — were built on generous lot sizes. Corner lots especially tend to have more usable space, better access for a separate ADU entrance, and more flexibility for placement and parking.
Why corner lots matter for ADUs:
More buildable area. Corner lots typically give you extra side-yard space that interior lots don't have, which means more room for a detached ADU up to 1,200 sq ft.
Separate access. You can give the ADU its own entrance from the side street, which tenants love and which justifies higher rent.
Better privacy. With the ADU facing a different street than the main home, both the homeowner and tenant get more separation — which means longer tenancies and less turnover.
Easier permitting. The extra footage on a corner lot often makes it simpler to meet setback requirements without needing variances.
I recently broke this down in a video on my Instagram — check it out here: Watch the Reel
