You can make unlimited money. find a shop that sells expensive stuff. Prowl (best if you're a master) and pick your way into the back of the shop. Now pick the chest and take everything worth good coin. Now sell it back to the shopkeeper. Rinse and repeat. You are on the road toward becoming a millionaire!
And why do you need to prowl and pick your way into the back of the store? Just wait in the store till night, and let the shopkeeper open the door for you, and follow him into the back of the store! In my current game, I just knock them out with some hexed items. Some that cause FT loss or poison. Then pick the key from unconcious storekeeps, or pry the key from their cold hands. I also plan to make a frontal assult on Stillwater (after I get my Dodge master). MUHAHAHAHAHAHA!
Well, sort of late in the game. All I have left to do is go to the void. I had no need for money, just wanted to see how it worked.