Being a fisherman, I'd opt for getting out on the water as opposed to sitting on a pier or some such. I've found easy to find decent shore locations to be fairly crowded. Being transient, limits what you can find, takes time to learn an area.
There are many inflatable and folding options these days, I've only looked at kayaks and canoes so can't comment on other styles. While I currently carry a solo canoe on the roof rack of my truck, in the future for distance traveling I may go with inflatable or folding. They won't fit in a glove box but they are a good option if you have storage room for one. With a 5th wheel I have plenty of room in the bed if I were to go that route. I'll probably go with a kayak as they look to handle the wind better, many a time I'm stuck on shore if the wind has kicked up with the canoe.
You'll have to look into all the styles available and see which fits you best. Your personal comfort level may decide of it needs to be a boat, like the Porta bote mentioned above, or if you can manage in a kayak or a canoe.
A Porta Bote style gives the most comfort and room, with a kayak having the least. A canoe would be between the 2 but feel tippy to many. Many trade offs between all the options, it's up to you.
Biggest issue to me is having to get a license in the different states, just not practical unless I'm staying in a given state for a while.
