Free boat for me - lots of questions
I was in a similar situation, having been offered a 25'' Catalina for next to nothing. It had been neglected for several years. I had the boat hauled. The boat yard scraped the ecosystem living on the bottom of the boat and discovered many blisters. They ground out and fared the blisters, painted the bottom, and buffed the gel coat. This cost around $2,000.
Find a cheap boat yard in your area and get a worst-case estimate.
I also had to buy an outboard. Check the boat manufacturer''s website for details about your boat. Catalina recommended a 9.9 long shaft outboard. I found a used one, but it was difficult. I paid about $400 for the outboard and another $400 for the boat yard to do maintenance on it.
Don''t have a survey done, it is not worth the money on a small boat that you are getting for free. If there is something major wrong with the boat, just sell it for what you put into it.
I put a lot of work into my boat. Be prepared to do alot of work yourself. I re-did the teak, and made lots of minor repairs. The total amount of money I have put into the boat is still less than what I see other boats like mine selling for. Make that your limit. Boats are like cars, they are not an investment, but an expense. However, you can have a decent sailboat for a little money. You will sail alot more and have pride of ownership.