CatalinaWOW: The best way to get a feel for it is to look for what things *sold* for, not what unsold items are listed for. Still, as you pointed out, demand - and accordingly price - can vary greatly for any number of reasons. As you, i just do this as a hobby and, at best, I hope to make enough to pay for the things I keep and to generally break even. But, taking the 5335 as an example: most places just buy one, take new pics, and relist. To go through and thoroughly clean and refurbish one - including not only the circuitry itself but actually following the manufacturer's calibration routine (and do it with in-cal TE) takes not only time but money. As such, I don't have a problem listing something at ~300.00 (and could certainly justify more) that I purchased for 100.00, but these guys don't even to wipe the dust off first - and, to list it at several K takes real big brass ones!
Hal