I have been told that if you are a Nevada resident you don't pay sales tax on a private party purchase of a RV for example..that would be a big chunk of change for us paying 9 percent sales tax... ...
Look into Pub 52 Use Tax Clearance. Very specific rules apply but even you in California can legally not pay the use tax (ie sales tax). Otherwise no you can't go to Arizona, buy a trailer, and bring it back to California without paying sales tax. Pub 52
