My first boat was a 12' aluminum jon boat that weighed about 100 lbs. Buying a trailer and hitch, etc. was going to put too big of a dent in the family budget at the time so I got a car top carrier and put a 1"x2" between them. I would lean the boat against the 1x2 and then lift the back and swivel it around to the length of the car. I think they now make carriers with a piece between them but a 1x2 or a 2x2 would certainly support a Nucanoe or a piece of schedule 40 pvc pipe. I would give the auto a good coat of wax on a regular basis to minimize the effect of cartopping.