Buying an auction property can be a bargain or it can be a pain in the ass. Important reminder is never rush in for any auction property, gather the information, do a check and make sure it's always at least 40-50% below market price.
Auctioned properties are mostly not in a good shape and often has lots of outstanding payment to be cleared off before you can get the title transferred under your own name.
In your case, if after paying the 20k, the auction property which you purchase is still a good buy, try to obtain some loan (company or personal) to settle it. If after adding up the 20k, the property is around the same or higher than the market price, please just let go and lose your deposit.
Just my 2 cents