Afraid I can't go that far for just a ride.
You can look yourself and look for signs of where the water was. It's almost impossible to remove all the stains so look in the darker corners if they are not obvious. I bet they are obvious. Look for poor attempts to fix anything as they should be obvious too. There really are an unlimited number of things possible and even on a boat not subjected to this type of disaster can have the same problems even if not actually expected or disclosed.
There may be more Catalina
30's out there than almost every other of boat made in modern history
. It means a few things. You can always find one cheap. You might find parts
easily. You'll find a lot of experience so that means help is available. They are popular too.
Given all that if the boat really isn't in that great a shape great you could shop some place else and be money ahead, time ahead, have a better boat, and with fewer problems. If this was a rare find of an unusual and desirable boat then you might invest in something like that.
I would go look and see what you can. Maybe take a few pictures and get a feel if it just plain looks like it has potential. Then do a quick yachtworld.com search on Cat 30's and see what is out there for sale
now. Given a pool of older boats of a similar design I say always go with the best one out there. Buying
the ugly sister does not save you that much money.
It follows the topic of the "free boat". We used to have the topic come up regularly but it has not for a while. The free boat bleeds you to death slowly and completely. Then you pay to have it hauled away. You just don't want to pay this seller to haul his free boat away. Once one owner is drained the rest follow even quicker.