If you have the ability to go to mournhold, there is an amazingly easy way to make 60k or more, selling the items takes longer than actually getting them. lol. When you find the Dark Brotherhood, kill them, and pile their stuff up in one spot, if you go into the North building, and leave, they will all be back. I killed them all in both buildings too, and cast recall to scampy in Caldera, fixed it all with hammers, then sold it, going from 32k cash, to 145k cash, took me two weeks in the game to sell it all, but I thought it was worth it.

Interesting tip. Methinks I'll move this to Spoilers though. ^^

Another way is to sell it to the armourer in Mournhold. He doesnt buy stuff for exact price like Creeper, but he has a lot of cash to buy stuffs with.