You do not get money back but yet you are bidding the higher amount which is taking from your pocket.
If I have $163 and bid on an item that is $63 I then have $100 left, but if I was to bid again on the same item without anyone else bidding, and I bid $64 I then would not get proof of a refund but I would have $99 left in my bank as it's only $1 more than the previous bid. If I was to bid again but bid $66 I would then have $97 because of the $2 difference in the bid I had previously.
You made me test this on my character with some low price item that I will never use! Lol