I currently borrow and have a perfect rating on btcjam and bitlendingclub (the forum I found this site on). I want to give this site a try and see if I like it better than the others.
I run a small online business re-selling inventory for other stores, our own inventory and inventory we buy broken, repair and resell. One day might look like we get a customer who comes in with a broken phone but doesn't want to pay to fix it. Sells us the phone for $40, we add a $10 part and re-sell it for $120. So you can see the margins are good.
Generally speaking we get about 3 times return on our money. Meaning if we had $100 to spend in a weeks time we would be able to make $300.