OP started this on 3-7.
By now he should have completed purchase - or not.
However - LOTS of poor -to bad- information.
Often -and usually- by folks in states other than CA, posting how it's done where they live.
Homework assignment - CA:
Correct - the Diesel MH does not need a smog check.
Registration fees - CA.....the BIG HURT is the sales tax. Depending on the county, it is right at ten (10%) percent of the purchase price!
Claiming you bought it "cheap" - won't help with newer RV - the DMV will use Blue Book fore valuation and tax.
CA *resident* Registering in AZ - or other state: CA wants the revenue! It is a violation of the law to do so - resulting in more grief than you can imagine!
That includes Montana LLCs !!
A MH with a MT plate in CA - is flying a flag for the CHP, which says "stop me" for any probable cause. Better have a MT Driver's License in the operator's name - NOT an LLC.
However - there is an easy LEGAL solution (which may de too late for the OP now): If a CA resident purchases a vehicle out of state, and keeps (USES) that vehicle out of state for one year (used to be 90 days), he/she can legally avoid paying sales tax. Franchise tax board will require receipts to prove same.
(hint - Be creative for "work-arounds").
The CA resident *will* eventually pay registration fees - but not sales tax.
CA may require verification of VIN to register for verification (in CA).
Any PD should be able to do that.
Look up CA "90 day rule" on CA dot Gov - applies to vehicles, vessels (boats), aircraft.
During that "one year" the owner will need to register it somewhere. Suggest South Dakota - or AZ since it's already there - whichever "price is right". (Check with Americas Mailbox, Box Elder, SD.) No need for you or the vehicle to be "physically" in SD to do same.
Maybe this may help some CA residents - and folks posting to "investigate" to possibilities.
BTW - BIL has had a smog test facility for years.
Two CA neighbors with new MHs - now registered in CA - pd zero sales tax.
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