I've had it happen a few times.The bank's addendum is technically a counter offer, so if you don't approve of the terms they are presenting to you, you don't have to sign it.Steph

After a few counter-offers, I eventually bought the house for 22,000.  

Assuming there's a typo in your post, a couple of things on buying bank properties:First, make an offer based on your numbers and stick to them, do not raise your asking price based on counter offers.  

He offered me $330,000 for my half acre on a corner at Dale Mabry and Interbay Blvd. two years ago to build eight Town Homes to come back with a counter offer after he sold his six Town Homes.

I started with a big fee, realizing that I'd have to counter offer.

Additionally, if I offered previously and the answer was No, I go back and offer again 3 - 4 weeks later and keep repeating until it sells to someone else or we can at least get into a counter offer situation. 

Hoping for some feedback - in the counter offer stage of this deal.

The property was in the process of counter offers when I called agent.

It took about 5 days between each time I made an offer or counter offer for them to respond - so a total of 3 weeks to come to an agreed price.

If they do want to sell they should present a counter offer.