[Yeow]

I would stay far away from D3 from a money making point of view. First of all, you're assuming that you have a class that can actually survive up to Inferno, and be able to farm it efficiently. No such class exists without first buying a ton of gear from the Auction house. You could potentially make a lot of money from D3, but you'd also have to invest A LOT, as in $100+ per item.

And be aware about transferring your money to paypal, Blizzard takes a 10% auction house fee on the actual trade itself, plus another 15% fee to "convert" your money to paypal.