Google Alerts was the key.
Set up alerts for Craigslist, eBay and everything else you can think of.
Use the "site:www.xyz.com keyword" search parameter.
Look for every keyword you can think of. "Roleiflex, "Camera" or what have you.
eBay will send an e-mail link to your gmail account whenever there is a hit.
I got a hit off "Gossen".
I asked the cop if he would let me watch him put the handcuffs on the guy. He laughed and thought it was funny.
BTW: Yeah, they clean out estates, alright!