He's right, down here there are a lot of abandoned boats in yards and marinas. The problem is they are often in really bad shape, otherwise owners or yards would have sold them. They've usually sat so long that they need substantial work, structural and otherwise.
The question you have to ask is, "is this boat worth the effort?". Even if it's free, you can expect to put several thousand dollars into it, probably more than you'd pay to buy one in good shape. If it's a high quality build boat, the end result may be worth having, but if it's not, you are just throwing your money away. You have to decide if the quality of the finished boat is worth the investment.
For example, I recently saw a NorSea 27 abandoned in a yard with no rig and no hardware, I figure probably $30k in improvements along with a lot of personal time to work on the boat. The end result, IMO, would be worth it. OTOH there was an abandoned Hunter that had the rig, and was in one piece, but probably wasn't worth the few thousand it would take to get seaworthy again.
Only you can make the decision on what to do, you have to decide if the investment is worth it. My personal opinion is that J-24s are a dime a dozen and you could probably buy one in better shape with the money you'd invest fixing this one up. They are cool boats, but not worth the time and money it would take. That's my opinion, it's up to you to decide.
that's what I aim to do today. see what it will take to fix. if I deem it too extensive, I will walk away. I notice, from the pic, it's missing hatches. that's a cost. it has new sails. that's a lot of money saved. sails aren't cheap even if you get them cheap. if the hull and all the things needed to actually sail are good, just muddy, then it comes down to the interior.
one thing that is for sure, regardless of how 'reasonably priced' and older boat may be, it is highly unlikely, without some miracle, that I will be able to afford one in the next 5 years. but, if this one is worth fixing, I can fix this one up. sail it now, and maybe, if I find one of those reasonably priced boats, in a year or two, sell this one to put towards the cost of a better one. i will probably not get my time or money investment out of it but that's not important. time is mine to spend and money spent over time, to fix something is easier to come by than money saved to buy a better boat. i'm not well to do or even comfortable. when I try to save money, an emergency always pops up to take it. but money spent is money an emergency can't take. I know that sounds illogical but it's how it works.
I guess I will see what the deal is wen I see it, in person. it might be a miracle for this to not be a bad deal but miracles do happen. earlier, this year, I got caught out on lake Marburg, in Hanover Pennsylvania, in a 30 minute squall. 30kt winds that blew in sudden 2' steep waves. I was in my 9' dinghy, of all things. but I saw it coming a few minutes before it hit and I managed to keep her upright and sailing to get back to the dock. it was a tense 20 minutes but I did it. miracles do happen. if you stop believing they can, life gets awful grim.
the question is: is this such a 'miracle'? time will tell.