Hi Bruce-
Depending on the seller situation, the bank may not be in control even if they did approve a short sale.
FYI- When a bank approves a short sale. And they give you a price, that is typically the lowest they will accept on this property.
SO, I would find yourself an agent you feel comfortable with. And have them negotiate on your behalf.
If you'd like to discuss the other answers to the questions you asked, please feel free to contact me directly.

Bruce don't be so quick to place a bid on $150,000.
Without working with a Professional you don't know if your bidding to high or not high enough. Feel free to e-mail me at gmetallo@comcast.net for more information.

You need a buyers agent assist you

Bank contract "ruled by bank" anticpate drama we have been listing/buyers agents no fault to any realtor bank norm of doing business.

Bank determine if your offer is accepted if not you may not receive a counter offer, banks dont have time waste for paperwork "going back and forth".

Realtor should do all research/investigation submit a winning bid for you.