Each bank/lender works a little differently, but they all have similar goals. They want to get the best price possible and have no interest in dumping real estate cheaply. Generally, banks have an entire department set up to manage their REO inventory.
Once you make an offer to purchase, banks generally present a counter-offer. It may be at a higher price than you expect, but they have to demonstrate to investors, shareholders and auditors that they attempted to get the highest price possible. You should plan to counter the counter-offer.
Your offer or counter-offer will probably have to be reviewed and approved by several individuals and companies. Even once an offer is accepted, the bank may insert wording like ..subject to corporate approval within 5 days.