I would be happy to answer your question, but can you tell me specifically what bidding sites you are inquiring about?
In general, most REO (Bank owned) properties typically accept the highest and best bid, which will result them the highest net. So, even though a cash or conventional loan offer could result in less time or effort on the Banks behalf, it is not necessarily their first choice.
I hope that helps, but if you would like to discuss it in further detail or need any assistance, please feel free to contact me.
Hulsey & Associates