Fix your the way the auction system is set up.
If I have 15,000 and bid 10,000 on someone I still have 5,000. So when someone outbids me I should either have all my money back immediately or I should be able to bid as if my 10,000 is still on the player being auctioned.
This is a great concept but needs to be fine tuned.
Oh and please move the coin total or the notifications to another part of the screen. It's a pain in the * when bidding and you can't see your coin count due to all the notifications.