The hunt is just part of the hobby. I've found some absolute great records in the "used" bin. My method for checking quality: examine jacket, record sleeves [many times old, well-preserved parchment-like is a good sign], check record for scratches/wear under good light. Does this always have great result? Well, no; but I have been satisfied more often than not. Example: Miles "Porgy & Bess", Bill Evans "Solo Vol. 1" and Wynton Marsalis debut record of the same name. Total outlay for all - under $10!
If you go the used route, be prepared to invest in a some sort of cleaning/restoration regimen. I use the Spin Clean RCM, then finish up with Perfection hand-held steam cleaner. Looks like Perfection brand is discontinued, but another good pressurized spouted steamer should work. Just make sure you have a way to protect the label from steam. I use a small "finger bowl" that covers perfectly. Hope this helps. Good luck and ...
Happy Listening!