Suspect some buds are fixed

I am a regular customer and I have received nothing but great service. Papers come on time and no issues. I only have one issue and my issue is that I believe ( though I have no proof) that gobid employees bid for cars to increase the prices. Why do I say this I have seen over 20 cars come back 3 times after I have come 2nd.who win the bids and why does it come back. I understand pple fail to pay and they bring it back but 3 times is suspicious.