"I wouldn't, it's like buying a reposession house. Money from misery. "
Oops, we did that. The house had been empty 6 months and the former owners had trashed the place. Yes we got it for a bargain price (65k instead of the 73k it was valued at) but that's just because the bank just wanted their "debt" back, they weren't fussed about making a profit. As it was, we had a few long-term problems with the house because of the ex-owners but it was definitely worth the money we saved and it was the house of my dreams.
As for pawn-shops - if it's a legit one (don't know if they have them anymore) where you have x amount of time to re-buy it, then they shouldn't sell it on. Normally (based on what my gran used to tell me) after that set amount of time THEN it would go onto general sale.
We've sold a couple of things to cash-converters in our time, not because we were hard-up but it was a good way to get rid of junk - got £40 for DH's old knackered N64 that didn't work (more fool them for not asking whether it worked or not and just thinking "oh the box is pristine, it must be fine" - eejits!)
Recently I had a look in a local cash-converters-style place (it's called Happy Hockers but the sign is written in such a way as to make it seem like it says Happy Hookers PMSL) but it was all over-priced shite. It's sad that people need to hock stuff like that... although not half as sad as those "pay-day loan" places you get where you can get an advance on your pay and then give them 150% for the convenience!