First question is if it has a vin
number that is readable on it anywhere youn know of. Actually that can be a negative. Also do you have documentation on the work you have done on constructing it? Reconstucting it? But you are going to want to call it constructing.
Here in Indiana I know a number of people who have taken trailer RVs with no title or title history and titled them. The procedure was basically to first get a police inspection that said it didn't have a vin
they could find and that it had no indication of being stolen. That is where not having a vin
helps. Don't like remove it that can get you in trouble. If in the process of building it the vin in some manner through a later documented process of the construction gone then that is legal. How the vin is pretty much always on the frame, adn one time it was stamped in the cabinets so if you removed that cabinet as a part of construction you were golden. I know that in one case the trailer jack was installed where the vin number might have been. But to make this work there in some manner legitimately has to be no vin number.
Once you have the police inspection you take that along with reciepts and documentation of construction or major reconstruction to the BMV. They then review the documentation and issue you a self constructed trailer RV vin. You then have to permanently attach it in the manner required by current law. They will given you a short pamphlet on doing that.
Most of my friends what they do is to take the vin number to an army surplus store. Most have machines to make dog tags. Those that don't know who does. They have a dog tag made up with the vin. They then drill the ends of it and rivet it to the frame.
Then once it has the vin properly attached to the frame you take the information for the BMV and the trailer to a police department again. Again you get an inspection where they will verify that the VIN is the one given and it is properly installed. You then take that to your BMV and get a title. Then the licensing and everything else follows the normal process.