Frankly they are MUCH less negotiable in most cases. I am REALTOR in Laramie, Wyoming and have worked many foreclosures (that's what we're talking about, isn't it?) I'm on their side and sometimes they won't do much needed things I ask as they won't spend the $.
Example: I had a house listed with no carpet. They wouldn't replace the carpet even though it made it much less salable. Not just from the buyer's viewpoint but also the lender's; an appraiser would call such a home (at least in my market) "uninhabitable". This means the types of loans available that the home qualifies for have been hacked down to a small handful if any (keep in mind, the buyer too has to qualify for the same type of loan).
I'm sure they lost money over this decision to not put in new carpet. I also had asked to have the house cleaned (it needed it), they wouldn't pay for it.
A bank in my experience will not negotiate at all or very, very little. They WILL drop the price as the subject sits on the market. But the second a buyer says "we want you to repair this" or "pay for that" the bank laughs and laughs and quietly says "no". My advice is, don't expect to negotiate on ANYTHING other than price. You cannot get most banks to do things, things lead to liens and liabilities and/or paperwork. Just figure out how to pay for x yourself and then hack x off the price and offer price-x or whatever price makes you feel satisfied. Hope that helps!
Broker, CRS, GRI, ePro
Raving Real Estate