: Seconded.

: A garage door opener has an adjustable force limiter, it should be
: able to hurt anyone or break boats; you should be able to stop
: it in either direction with one hand. It should reverse when
: halted in the downward direction and stop when halted in the
: upward direction if I remember correctly.

Yep, even the old openers shouldn't have enough down force to do more than scratch the boat if lowered onto it. Newer ones are much more sensitive and shouldn't hurt the kayak in the least. Normally down force is pretty easy to adjust and even if you don't have the manual for your opener anymore, most are available online.

Bill H.