I've found several 35mm rangefinders and slr's in charity shops. There is one next to where I work, so I'll be scouting almost daily.
One time I got 5 box cameras for free - otherwise, they would have thrown them out.
Yesterday, I found an Olympus Trip 35 from 1967, in excellent condition for about 1,5 £
Still waiting for a Hasselblad to show up. ;o))