In order to submit an offer, you have to have a pre-approval from you bank anyway. So I have no clue what you are talking about.
With bank owned reo’s be sure to keep at them. Their computer won’t let them take your low-ball offer too early. BUT, when the comps start rolling in with around the same PPSF, then the bank will take it. It also helps to run comps yourself (or your broker), do a 5 mile radius and only include sales in the last month. THEN submit that with your offer. The great thing is that will pick up the short sales, and that will get bank motivated.