I just came back from spending a few weeks with my mom and saw this thread. She had a commercial art studio and publishing house for years and both my myself and my dad did a lot of shooting and processing for the business. He got into serious camera collecting in the late 70's. About 90% of the collection was aquired through garage sales, flea markets, and a number of pawn shops that seemed to be happy to practically give the camera away.
He passed away in 2013 and I have been inventoring his colletion of about 400 cameras. He had just about everything; Brownies, 110 instamatics, 126's, 4X5 twins, 35mm, Polaroids, The most valuable, and interesting part of the collection, are the sub-minatures, many of which are actual spy cameras from the early 1930s through the cold war. What is interesting is that many of these little cameras had film cartridges the size of a watch battery.
Others are small cameras that were given away for promotions. I have one pinhole camera that is the size of matchbox, that is still in the original mailing package, that was sent to lady in 1926 for buying a term life insurance policy.
Camera's, like just about anything else, do have a pretty large market for collecting depending on age, make, and condition. I can say this, don't just throw one out. Camera collecting in growing in popularity. My dad mentioned many times that in the last years of his collecting, is was getting next to impossible to find "cheap" old cameras.
I too have a good collection of Nikons that were our working cameras. F, FG, FM, and FM2s. Been looking at getting a digital converter back for the FM2, but cost and performance has seemed to been a drawback. Still, those bodies seem to be holding values over $100. I did aquire a D7200 that I started to use.
Mom, at 82, still works, but the whole studio now is in a bedroom and consists of four computers with full Adobe and Coral suites, a Wacom digital drawing board with a huge collection of pens, brushes, and even an airbrush, and a number of high end printers that can reproduce a complete oil painting. Digital technology been a blessing for the working artist and photographer.
Scott