Dude, the Chesapeake is not the Gulf of Mexico
Also, the guy from CA - KnotFoundering has a 16.5" boat which is probably dry sailed or on a trailer most of the time (eg., his hull is always clean - no offense intended KnotFoundering as I still also own small boats like yours - a 14' and and 19' sailboat, if you check my profile). I had MAJOR barnacle buildup on my 19' Lightning last season as there was no real anti fouling paint (the boat had previously been 'dry sailed') and I moored it in salt water and the barnacles built up to an incredible degree - still not chucking the boat because of that. Lots of elbow grease will get that off (without sanding) and I will repaint it and keep it in salt water once again. Landsend has it about right: it will cost money and time to fix each year (as long as it is worth it to you) and pay for the off season costs. Seadaddler has recently retired and bought a brand new boat and probably pays others to take care of his own bottom jobs. Sorry if I am misreading any of your perspectives.Frankly, I am glad to hear that it costs $31/foot of boat for just painting in CA, KnotFoundering as I do a lot more than just re-paint every year and have a boat partner I should bill for my services. $10/foot is just too damn cheap for the nice job I have been doing on my 27' boat and we even won a race at our club and part of that is due to having a clean bottom.I love 'classic plastic' sailboats and even like woodies but I am not that crazy (or rich enough) to bother owning one. A 1982' sailboat is 15 years younger than my 27' sailboat and should otherwise be in pretty good shape. Get them to knock down the price for restoring the hull.Even if the swing keel/centerboard is stuck due to barnacles you can get it unstuck again with the proper tools. You need to find a piece of metal that will fit in the slot and crunch out all the growth without severely damaging the slot. All it takes is elbow grease and having the boat on the hard for long enough to do it. Check the prices of comparable Catalina 25' swing keels on the web that are ready to sail and go. Figure out how and how much money it will take you to get the boat to someplace you can work on it and deduct your start up cost from the asking price of a ready-to-wear C25. The previous owner (PO) should end up owning you money if my thinking is right. You need: sails, boom(? - you did not specify what rigging is missing), new battery, engine tune up (and a hole lot of other things to make your trip to the haul out site possible - hand held GPS and VHF would be nice). I see no reason that the hull of a 1982 Catalina 25' should have blisters in it other then it has been left in the water for X number of years. If you are serious about this then you should get a mask and snorkel and dive the bottom of the boat to really figure out what is going on down there. You should try to scrape off the sea weed and slime a few hours before you even attempt to look at it while looking for blistering or bulges in the hull surface.Owning a boat is a labor of love or an expense of a lot of money if you are willing to pay people to do it for you. I do not know your circumstances but if you want to do it on the cheap you might be able to get the PO to sell it for real cheap (say $500) as he already owes back dues to his marina (cost mounting every month) and just wants to get rid of it and reduce his monthly/yearly costs since he ain't using it anyway. An example: my friend who keeps his boat in Mayo, MD recently sold his Hunter 25.5 for around $2500 but it was in good working order with sails, rigging and working engine. It will cost you about $2+K to get some used sails and re-do the bottom if you do it yourself.There are a lot of boats out there that you can look at so I should not be so dismissive of those that recommend the "run, don't walk" attitude. It is ultimately your own decision. It does not sound like a bad boat though and might be worth pursuing if you are willing to put the time and energy into learning a lot about your new (old) vessel. We (as a group) paid $4K for our 1967 Tartan 27' over 5 years ago. It was in sail away condition but continues to require yearly maintenance that is easily $1K per year, plus upgrades. Do you have a marina or anchorage in back of your house that will cost under $1K per year?Advice is, as always, cheap. Your mileage will vary.Good luck.