Check your state laws. PA requires you to get the assembled trailer weighed and then inspected. I got my first trailer weighed after putting a plywood deck on, and the inspector questioned why the weight on the shipping slip was different from the measured weight. That ~60lb plywood sheet was the difference and the inspector OK'd it.
I'm skipping all that B.S. this time, and registering my new trailer in Maine as a non-resident. No inspections, no weighing. Just a few pieces of paperwork and a check for $10.50
EDIT:: Found this in another forum. Sounds easy in MI