If you go with a trailer, and that's my suggestion to you, look at the
Malone Sport Trailer..
This trailer will handle a 20' kayak as is. It has real wheels and tires unlike the Yakima trailer. And it handles rough roads very well.
I kept my eye out for a used one and finally found one for half price. Very happy with it, so far, for our 14' and 11' kayaks.
We went through the decision-making process on how to take our kayaks with us: roof-top, vertical (not applicable to your situation), or trailer. The trailer won out because
--we don't have to buy and mount a roof-top kayak rack
--we don't have to climb up on the TC roof to load/unload the kayaks
--we don't have to remove the kayaks to crank up the roof
--loading them on a trailer is easier and faster.
--we found a good quality trailer for the right price
Hope this helps.
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