Thankfully, the seller's agent has very little input in the decision! The bank/investor will usually ask for the "highest and best" from all offerors. This is the mystery...the highest is not always best and the best is not always the highest. The Asset Manager for the bank makesthe decision.
Hopefully, you trust your buyer's agent to get in there and really negotiate on your behalf. I should probably ask if you called on a sign and went with the listing agent for your offer...as that is also not always best. This is where you need someone to advocate for you!
Of course,you can always check the l/a out on the Calif dept of Real Estate website http://www.dre.ca.gov
and click on license lookup. Enter their name and city to bring up their recordsand check for violations.
One more hint...there is a very disturbing trend with banks that they are really being stubborn and not discounting these properties like they should or could. So, that means that you really can't "steal a deal" so much. The common perception form the media is that prices are so low and the banks want to get rid of these foreclosures. The truth is far from that. If you lowball an offer, you run the risk of losing a home that you really want. They will simply accept another offer without giving you a second chance. Now is not the time to try and play the Real estate game.
Make a reasonable offer and expect a counteroffer, and you stand a better chance of success!
Good Luck in your purchase.