There is a slight glitch with the upgrade screen. If you have an upgrade point left when the end of a day happens, you lose the points when the day ends.
I think an interestnig concept that might work well into the whole auto-buy/auto-sell thing would be to put a delay before the selling of items to work with the auto-equip feature, much like with what happens with the chests.
I hate games that force you into paying real money to own guns permanently. It turns an otherwise great game into something that is only truly enjoyable by those that have the money to dump into the game.
I may have found a glitch in your game good sir. You can just continuosly buy the ruby equipment. Wasted about 10,000 thinking that I didn't have it...