What I do usually is: I buy camera for couple of euros on flea market, play a little and then to big auction site start from 1$. Most of the time I got even, sometimes I lose a buck, sometimes I win .
Last one that I got is some lomo plastic toy with 4 lenses, funny camera.
Not a flea market, but a yardsale - and it was on the "free" table.
A Kodak Carrousel 850 w. 4"/2.8 lens, with cords, fresh bulb, and two slide Carrousels. I did end up walking about three miles with it...
I recently picked up in a yard sale also, a Minolta X-700 35mm camera w/ Samyang MC Auto Zoom 35-70 mm 1:3.5-4.5 , and a Tamron 70-210 mm 1:4-5.6 Zoom and a Tamron 2 x AFI BBAR MC7 tele-converter for $40.00. Everything in mint condition, almost finished with my first roll of film with it.
The converter not useable as-is for the camera, so need to find an adapter or, trade for one that will fit.
Scanned 8 by 10. little shoreline, big sky in sunny Florida. Chinon Memotron 11, Mamiya Sekor 21mm lens at f8. On Polypanf at asa of 160, 12 min in d76, one to one at about 73 degrees F.