Should North Tustin get its own ZIP code, it’s possible residents wouldn’t be on the hook for quite as high of a sales tax. The base sales tax in Orange County is 7.75%, for example.

Among 84 local ZIP codes with sales, prices increased in the past year in 62 and decreased in 22. Priciest ZIP? Newport Beach 92661 has a $7.2 million median. Cheapest? Laguna Woods 92637 at $539,000.