Party wall: common/ lot retaining wall

Hello: PA location

This question involves 2 separate retaining walls, in the middle of which is the townhomes entrance block (cement structure off of the home that leads into an entrance way). The retaining wall is on common property; however, the HOA is reporting it is part of the lot (note: the wall runs parallel and does not cross into the lot). One wall is about 20ft high and 30 feet long. The other is about 20 feet high and 15ft long. The wall does benefit the homeowner in question, but also holds back a lot of "earth" for the units below/ next to that end unit. Is this indeed a "party wall" or completely a common area wall. And who's responsible for repair and maintenance of this wall. One of the walls is failing.

You would have to study the plats and declaration to see if they provide clear guidance on who "owns" the wall and is responsible for its upkeep. In the text of the Declaration/covenants, look especially for verbiage on "walls."

If the plats and declaration are unclear, then you will have to hire an attorney.

I would hire a surveyor to see where the wall is on the property line. Run a Title search to see
who and when the wall was built. The title search may include multiple property lot searches.