Boat not properly winterized

Looking at used boats and the marina said the previous owner didn't properly winterize it and had to replace the engine. Doesn't sound like any other maintenance was done to the boat. Should I be worried about having to fix anything else due to poor winterization? Is it not smart to buy a boat that had to have the engine replaced? Or is it just hell on earth keeping up with other maintenance issues like vibrations throughout the engine prop transmission etc? Obviously there's a concern if he didn't properly winterize it what else did he not care for...