It is not list price that is an issue it's market value. Anyone including banks can list at any price. We just closed on a FNMA forclosure about 20% off market value. Buyers still bid below asking, but got about the same $4000 off. They might have paid list to get it though. One of the cleanest foreclosures I've seen.
Often it just depends on the deal and what their BPO came in at. Sometimes those are right on the money and should account for needed repairs and market. Sometimes they come in low and sometimes high. Asset managers are busy as are the REO agents, but I would normally expect a response in 24-48 hours. Your agent will have to call and call and call and email and fax, to make sure the bids get entered. If at first you don't succeed keep trying. Resubmit after a couple of weeks if you don't get an answer. Things change.
Also don't expect to close on time. Everyone on their side of the transaction from agents, to title, to asset manager can be painfully slow or non-responsive at times as they are extremely busy.
I am curious as to whether you are working with an agent? The reason I ask is that is the only way you can get a good market comparison to actually know what the market value is. As far as what you should negotiate depends entirely on the market value of the home. If the list price is truly fair market value and the bank responded they may not make another counter. I know in some of our recent negotiations once the bank countered the first time they were done. That may or may not be true in this case. Good Luck we hope you get the house!