Investment?
I don’t see it as protecting my investment- I can always buy another boat.
But if your boat goes through someone’s windshield at 70mph, the lawyers will likely see to it that you’ll never afford another boat.
Make up lines to length for each boat. Use carabiners to clip in to the transport vehicle. Then a quick couple of hitches and you’re done. Takes maybe 2 minutes- you owe it to the other folks on the road.
Pete in Atlanta