I have very limited experience with bottom painting boats, although all of my boats have had bottom paint on them when I purchased them. I don’t mind the look of the bottom paint on my current boat, or at least it’s grown on me, but I like the look of a boat that hasn’t been bottom painted much better. I do think that bottom paint can be very useful when you moor your boat for months on end, and mine has been in the water on our mooring buoy for just under 2 months now. Of which, it’s just now starting to get some gunk above the waterline and above where the bottom paint line is. I believe my boat had brand new bottom paint on it when I bought it from the dealer last October, which is nice that it seems to be working pretty well, although I don’t imagine most people leave their boats in the saltwater year round, or for 3-4 months at a time, though I could be wrong.
I have however, seen boats that weren’t bottom painted that looked like they’d been in a marina or on a mooring buoy for months or more at a time and the hull looked like it was turning a brown/orange color from the amount of growth in the water. Hopefully that can be removed and it doesn’t cause any permanent discoloration of the hull, but it did look pretty gnarly. I also noticed when I bought my boat from the dealer I purchased it from that they had a sheet for “current bottom paint pricing” of which my boat I believe it said it was around $800 to do so. I’m sure it’s a bit more money for doing it the first time as I’m sure there’s a bit more prep work and details that you have to go over, but for less than $1k to have it done, I likely wouldn’t even consider trying to do it myself, especially if they do a nice job, use quality materials and can get it done in a week or two. I’m sure I could probably figure it out, but I’ve never tried it before, and for the hassle as well as lack of experience, I’d leave it up to those that do it for a living and will make it look much nicer than I likely ever could, especially for not too terribly much money in the process.