Used weights are usually pretty easy to pick up from pawn shops and the like. Brand new sets of barbell plus weights aren't prohibitavely expensive, either. Usually only a $100 or 2 for a very basic set. dumbells can start to add up just because you need to pick up so many.
new barbell set $100 at
Dick's Sporting Goods.
adjustable weight bench (no pins) $80 at
Dick's
(not an endorsement for Dick's, they just happen to be closes to where I live)