Don't pay anything. the seller is anxious to get out of the place since he is financing 100%. You make sure you see all of his books and tax returns for the last two-three years. Also, make sure you have an asset purchase and not a stock sale, since you don't want his debt coming with the purchase. The more I'm thinking about it, make sure you hire a NON-pool playing attorney that will look at facts and numbers and not be awe struck that you will be buying a pool hall!
Good luck. Sometimes I miss it.....
Bob