Repairs in the game inherently inhibit progression, the cost > gold income by a large margin.
I also find that despite having good gear, unless your in the top 1% you wont be "farming" act3/4 without issues, and unfortunately because of the games economy getting into that 1% requires a ridiculous amount of gold (100's of millions).
I've hit a brick wall with my monk, I can do ACT3 fine, I've killed Diablo with ease but my progression gear wise has stopped. I'm at 36k hp, 34k dps, 740 ish AR but ACT3 still results in enough deaths to make it pointless.
I can go back to act1/2 and steam roll over them in a desperate attempt at getting 1 sellable item, but as upgrades for me are well in excess of 20m+ a pop, it would have to be a godly item. Which are as likely to drop as being struck by lightening twice, on the same spot, while wearing a tutu and singing bohemian rhapsody.