It would appear that the HOA is suing you for the time from filing a BK to the date the mortgagee had its judicial sale. If they have not served you they should not be able to obtain a judgment. A lawyer at this point might be able to obtain a reasonable settlement. During the negotiations he does not have to tell them where you live.
When you file bankruptcy, all indebtedness owed prior to the filing to the homeowners' association should be discharged. However, any HOA dues which arise after the filing while you have legal, equitable, or possessory interest in the home are not discharged. Unfortunately, it may be possible that these debts were not discharged because you have a legal interest in the property.
Whoever is the legal owner of the property - that is, the person whose name is on the title - is the one who bears responsibility for this indebtedness. Although you state that the property was foreclosed on prior to the bankruptcy, there is a possibility that the bank has neglected to (or intentionally failed to) actually record the deed from the foreclosure sale. In the last few years, more and more foreclosure sales have been left unrecorded because it is simply not profitable to record the foreclosure. Unfortunately, since this leaves title in your name, you are the one having these fees assessed against you.
If your property was transferred out of your name prior to the bankruptcy, then there should be little that they can do to try and collect this debt. However, you should consult with your bankruptcy attorney, or another qualified attorney, to determine whether these debts were post-petition, and if so, what options you have available.
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Roughly, how much are they suing you for (if you know)? This may help you determine how serious they are about collecting, whether they're willing to negotiate, and whether it make sense to retain an attorney.
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