Totally new to auction.com

[Mina Kicsi]

Hi guys

Friend won a bid on auction.com and do not want to move forward with the contract. Immediately  realized that Overpaying for the property... there was a buyer premium extra +$ 13000 couldn’t see on the phone screen when placed the bid. Also first timer without bidding experience....Can he back out without any penalties? They sent the contract over but not signed. 
Property data was inaccurate  including number of bathrooms, estimated re sell value etc.

I appreciate your advice here...