Thanks, Waste. I guess my next step is to drain the sucker and pull the liner out (it's about 15 years old, so it's about due for replacement anyway) and see what I'm dealing with. I'll have my brother (he's a carpenter) come look at it for his expert opinion, and see if I can get a pool installer or two to come out, too.

Any suggestions on what to look for or to ask?

One problem I see is what to do about rain while I have the liner out. I don't want anything that's still good to be ruined by water.