Wowww!
We have one of these dolly things! They’re great! It’ll be a little while before I undertake this project (and I’m still browsing Craiglist for cheap trailers I can make work, but I promise to post pictures if I can recreate this! Thanks so much!
#goals! Now I truly believe this is do-able. Maybe there is indeed a way to attach bars to my rack (I was thrown off by the weird retractable crossbars on the factory rack) and add a trailer hitch attachment. Thanks!
Thanks for sticking up for the Grumman! 
It’s a square stern and a motor and sailing kit are next on the list of accessories so we can truly enjoy it to its fullest.
Wooooooooooah! Haha, this almost makes me feel silly for asking about help for a 19’ boat. But I’ve gotten so much great advice that I could never feel silly. Thanks for the photo!
I have a trailer and it really is nice to only lift up to waist height. And I’m only moving 45-60 lb kayaks. But there are a lot of launches that just don’t have good parking for trailers and because of that I also have a roof rack. You often have to park further from the launch if there’s even any trailer parking at all. At one Maine launch I use, the sign directs you to use a lot in town that’s a mile away.
A boat trailer is the easiest to work with since it will have a long tongue. Just keep watching. I see workable looking trailers come up in the $300-400 range fairly often. I’m on my second trailer and the first cost $95, the second $300.
There are trailers for any sized boat.
Trailers are great, but like most things they have pros and cons. A couple cons that come to mind having owned several trailers, first they take up as much space as having another car and need taken care of. If you back into water when launching the wheel bearings should be pulled apart and greased every so often. They have small tires so when your car is going 60mph the trailer wheels are doing more like 120mph in terms of rpm. Last thing you want is a wheel bearing going bad on the highway. Old used trailers are cheap but you should go over them before trusting them to be ready for the highway. Second trailer lights are notorious for acting up with bad grounds being most common. Then there is the cost of plates and annual registration. Backing a trailer up that’s low is tougher than most people think and as mentioned finding pull thru parking is a problem around here at canoe launch locations and I try and stay away from the large power boat launches as they are not setup for little low boats.
Now if you have a 20’ heavy canoe and you plan on adding a motor and getting the boat registered as a power boat, then hauling it on a trailer and launching it as a power boat at public ramps is logical.
In Maryland, in every county but one it is generally free to park and launch a cartop boat at public ramps and launch sites. If you have a trailer you usually need a day or seasonal permit, which can be fairly expensive.
Keep in mind additional toll and parking fees.