I know nothing about the legalities of transporting boats interstate.
I have moved lots of boats, and loaded more.
As far as the actual process, it depends a lot on the boat. A small boat might be sitting on a trailer, and one of the companies that brokers towing travel trailers around might be a source of someone to tow the trailer.
A bigger boat is not an easy load. It might be overwidth, length, and height, requiring special permits, daylight operation, special insurance, and an escort vehicle.
Most boat haulers use special trailers that include hydraulic pads or screw jacks to keep the hull upright, and are built very low, sometimes with a lengthwise slot in the trailer to allow carrying the keel very low. Sailboats with deep keels and powerboats with flying bridges get very tall. Removing a flybridge is a surprisingly big deal, mainly to do with the wiring and controls to the upper steering position. With a sailboat, loading and lashing a mast without mangling it is not as easy to do as it looks.
BUT. IF the boat is in a place where there's a "Travelift" the Travelift can pick the boat up and set it on top of a flat deck trailer. A good rigger can build shoring to hold the boat upright. At the other end of the haul there has to be a travelift there, too. In the old days when most boats were stored sitting in their own cradles it was possible to load a boat by jacking it up, but that's a pretty specialized job, and requires a small mountain of blocking, which is usually 6X6X42" pine to build cribs out of, and a couple of 12' timbers strong enough to carry the weight of the whole boat.
The big company that had ICC "rights" to move boats interstate was called "Boat Transit." The other was called Kenosha Auto Transport, or KAT. I just looked on the internet, googled "boat transport," and there were a bunch of vendors there, including one that specialized in towing boats on trailers.
Hope that helps.
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