When I registered my 13' Scamp
in Calif in about 2004 I was given a 'Permanent Plate" without asking. I think I have been charged once more since then, permanent means something like 10 years. It may have to do with length, weight
or lack of "plumbing" . I don't remember if they asked about plumbing. You don't need a 'Pink slip' (Calif St registration) . You can buy and resell with only with a bill of sale. I paid something like $16 extra to have the official Registration
papers. I've sold lots of trailers with only a bill of sale, but they were all cheaper trailers or utility trailers. I would hesitate to buy an expensive or nice trailer in CA without a real Registration
Certificate. David in Fresno and Sonora, CA.