Used pool tables are frequently available. Keep an eye on your local classified section for moving sales, yard sales, estate sales, and so on. Youre sure to run across something eventually.
When shopping for used pool tables, ask all the same questions you would if you were buying a new pool table. What size is it: 7, 8, or 9 feet? What are the body, bed, and cloth made out of?
If the body is made out of more than one piece of solid wood or other material, check the connections for wear and tear. How sturdy is the table? Crawl underneath the table and have a look, as if you were a car mechanic. Stand next to the table and give a shake or two, back and forth, and side to side. Bring a carpentry level with you. Set the table on even ground (as gauged with the level) and test the bed with the level. Shoot a couple of games of pool on it. How does the action feel? Is the ball trajectory hampered by inconstancies in the felt, either on the surface or in the cushions? How well preserved are the cushions? Do they have any tender spots? Are they sagging anywhere?
Furthermore, ask whether the bed comprised of one solid sheet of slate, or divided into three sections...