Get as much information as possible together and go see a lawyer. Your best recourse may be to go against the banks on some negligence theory, but it sounds like a real mess.
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Maybe, but it sounds like a huge mess. You should speak to a lawyer ASAP, and keep in mind this is going to be no simple matter. The exact equity in the house should be significant, or else, I don't know if it would be worth it.
This is a matter you will want to discuss with counsel. To make any consultation fruitful have as much information and documentation you can. It is easier to piece together what has happened and what if anything can be done.
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