I'm confused. Why would anyone trailer an FJR when they could ride it? I saw a trailering of less than 500 miles which confuses me even more.
The options are:
1) Fly, bus, train, or rent one-way then ride unseen motorcycle home.
2) Get someone to drive you there, and spend the night.
3) Truck or trailer the bike home.
4) Pay someone to truck or trailer the bike home.
400 miles each way necessitates an overnight stay.
All too often a round trip airline ticket with Saturday overnight costs less than one-way. Tell them you have overnight stay on a Saturday even if you don't intend to use the return flight.
A U-Haul pickup truck or van is $20/day plus $0.69/mile (expensive). Motorcycle trailer is $15/day.
No shame in trailering if that is what one must do. I would use truck or trailer, or borrow a friend to drive, in no small part to ensure I have a paid-in-full exit if the motorcycle was not up to snuff.
I'd trailer it 400 miles, but then I have trailers. Beg or borrow one or even a pickup truck will do (borrow some ramps). Riding a bike home that I know nothing about, well, wouldn't bother me that much, but I'd rather trailer. IF it has a stock seat, 400 miles will feel like 800.