The titling law on NJ's website is out of date for some reason, two years ago new legislation passed, and having a phone conversation with Trenton's DMV is the best source of information because the local offices are somewhat clueless as to the ins and outs of titling weird stuff.

Yes, NJ allows homemade trailers, but you have to have it inspected in Trenton also. This type of inspection is not a "walk-in" service, and instead you have to call ahead and make an appointment.

Once it passes inspection (rust, welds, tires, lights, chains) they'll send you to the local state trooper building who will assign you a vin. Then, you go back, title the trailer as you would any trailer, and you're done.

The same process applies to homemade vehicles, kit-cars, except that to get either to pass you have to show your welding certification with a date that's at least a decade old - so they know you can weld and it's reasonably safe, since they don't x-ray the welds and simply go by what they can visually inspect (which hopefully is covered with paint).

NJ does not accept bonded or glued together kit cars or homemade vehicles, even though body shops do this regularly and those kind of repairs are within the law.

Go figure ;-)