A 13" Scamp falls under what Ca. DMV calls a PTI plate.
It's a permanent registration
that cost $10.00 for 5 years.
It's called a paperless title
If you want an official title
that will cost you an extra $15.00.
There is a special DMV Bill of Sale form for PTI trailers.
If you sell it out of state you may need the actual title.
Virtually any trailer 16' or under qualifies for the PTI registration
It's the ONLY good deal you will ever get out of the State of California.
If your DMV has never registered a PTI trailer you may have to have them call Sacramento as I did the first 13' Scamp I ever registered.