I have owned 12 boats (row, outboard, inboards, and sail) since I was 16, in my 60s now, I bought some new, most used, and all but one worked out fine, they all were used in saltwater and in good shape when I sold them. They gave my family, friends, and I countless hours of enjoyment fishing, sailing, and cruising the waterways.
My 1981 Boston Whaler has lived all it's life on saltwater, the original engine was replaced about 3 years ago. So I think boats are great.
Get an experienced boating friend to help by looking at some boats with you, keep a cool head while looking,
Don't get romanced by the first one you see!
Good luck!
Steve W