It's a catch 22.  I like to sell my machines for top dollar, to invest in new stuff, but I like to buy cheap.  They aren't compatible, which makes it such an interesting hobby.  I bought an iPad for $200 and sold it for $300, and a Mac Mini for $250 and sold it for $400.  Take out the fees, and I had enough left over to buy a boxed 3.5 External Drive and a boxed Macintosh IIe card (yay, I finally freakin got one!).