I heard that there are companies who read through mortages with a "fine tooth comb" looking for anything that may invalidate the mortgage. We are in a situation where such a service would be helpful. Does anyone have any info on these companies, their contacts, and if they've been successful? Thanks

I have never heard of that type of service. My suspicion is that it is a scam. You pay for the service, then find out your mortgage is valid.

If you do find something that would invalidate the mortgage, it is extremely unlikely that you would get to keep the home. I would suggest looking for a more realistic alternative to deal with your financial concerns.