Is level 40 the max? I'm no longer gaining XP. I thought this was supposed to be endless?
Also, I think there's a bug with selling items. After a certain amount of +cash% it's impossible to run out of money as you can sell items for over 400% of their value. (even ones you buy from the machine)
I have $3 million and can't find anything good to spend it on. The guns are too weak and there's no way to increase my damage with them.