Thank you for your question and I'm very sorry to hear about this situation.
The fact that the HOA is refusing to provide you with a copy of the by-laws and is refusing to send you an invoice for the fees due is very odd and also means that you do not legally owe the late fees they are trying to collect.
However, the fact that this is an HOA means that they will collect by placing a lien on your property and attempt to enforce the lien through foreclosure
This can be a very costly situation to resolve and also places undo pressure on you to acquiesce to their demands. In order to avoid this situation you need to act immediately.
What I recommend that you do is file a Declaratory Judgment
Action, in which you will have a court declare that you are not liable for any late fees, that the HOA is required to invoice you for any dues and assessments, and that the HOA must provide you with a copy of the by-laws and allow you adequate access to the HOA records (as is generally the right of any HOA member). In this Declaratory Judgment Action you would also ask for a temporary injunction to prevent the HOA and the attorney firm attempting to collect from you from exercising any collection rights such as foreclosure, until the matter is resolved in court.
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