The most fun I've had doing this sort of thing is going to goodwill outlets (aka "the bins" ...of crap) and looking for stuff to flip. You pay by the pound, and the more you buy, the better the per pound rate. And your helping out goodwill with landfill costs. And your reusing something that would otherwise be trash. Everyone wins!

You would be astounded at what you can find there... things worth well over 100 dollars show up regularly.