We've had a steady stream of people who've done what you're thinking about, and it has not gone well.
It's hard to get parts; pool guys will NOT help you work on a used low-budget pool; there tend to be hidden things wrong, and more that WILL be wrong after you move the pool.
I would recommend that you not even CONSIDER purchasing it, unless you have $500 for the pool AND $1500 for the installation and repairs. You'd probably be better off getting an Intex Ultra, like this one at Amazon:Intex 54955EG 18-Foot by 52-Inch Ultra Frame Pool SetYou still may spend $400 on site prep and such, but you'd have an all new pool. They seem to last at least 4 - 5 years with reasonable care.
In my opinion, used AG pool purchases are best left to experienced handy men and tinkerers who have spare case and time, and who are making the purchase in the FALL, not in the late spring.
Sorry.
Woah! Just re-read your post: a 20 year old AG pool? FORGET ABOUT IT!
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