Instead of just dumping the unique items that you cannot sell in your current act, if you bring the items with you to the next act, you can sell them there with no problem. It would be nice to sell them in the current act rather than waiting until the next act in order to sell them, though.

"There's a great many people in this world, who through no fault of their own are sane." However, I am not one of them!.......Tomcat