this is for sale in my area, is it worth the trouble?

NecioVato

since you reached out to the shop who worked on it - have you asked them a 'rough ball park' as to what it would cost to get it back up and running? Full disclosure - not so handy with a wrench - but - is this the type of issue that could lead to 'going down the rabbit hole' chasing other issues that might pop up after this initial issue is fixed or.....once this is fixed - you are pretty certain that it will be running like it should etc.
I've always wondered what it would be like to get someone else's build especially if they are adding parts etc that I would do anyways - allows for one to save money on mods and it already being installed etc - yet....as they say you might be inheriting someone else's problems. Goodluck regardless