Get your boating license first. After that, try renting a boat for the summer or piecemeal. Try washing it, refueling it, doing an overnight to another city, etc. If you like it, you can buy one next summer. If you dislike it, or don't think you'd do it as often as you thought, you saved yourself a lot of hassle.
I worked on boats a ton and got to know the ins and outs of maintaining them. Bit of a pain in the ass, but they are quite fun. Decent amount of hidden costs. It's a fairly investing hobby, close to (but in some cases, not as expensive as flying a small plane as a hobby. You'll spend a lot time working on the boat to keep it in shape for excursions.)
Cleaning motor boats is a lot easier than sailboats. And if it were me, I'd make sure it was able to be trailered, and look into how expensive fuel, maintenance, insurance and most importantly, slip fees and places you can moor your boat at other harbors. If you don't wanna pay sticker, look at the used market. A lot of boat owners are sick of paying slip fees and might part with it for less money. The flipside is that they might take a ton of cleaning and maintenance to get back into shape.
One final tip: do not exceed your fuel range, and make sure there are multiple places to refuel if you are going camping in a remote location (eg, an island chain). Some fuel depots might not be operational or have limited hours on weekends or weekdays, unlike car gas stations. Our neighbors got stuck for a weekend out in the islands when the lone fuel depot was closed on weekends, and they didn't have the range to make it to another island.