You are (considering) buying a property and intend to receive the benefits of ownership (possession) as bargained for. 

Then I filed for possession.

The property is being sold subject to: All taxes due the municipality not foreclosed by this action, Water and sewer use charges not foreclosed by this action, All building and zoning regulations of the municipality which affect this property, All building lines, easements, restrictions and all other matters concerning this property which appear of record, The rights of any person in possession or occupancy of the property who have not been made parties to this foreclosure action, The right of the United States of America to redeem the property, if applicable under Federal law, Any other liens on this property which have not been foreclosed by this action.

Under Georgia law, if a tenant has actually abandoned the property then you do not need to obtain a writ of possession.

Pursuant to a written lease (the "lease") dated xxxxx, you are a tenant for the premises described as xxxxxxx (The "Premises"), of which you now hold possession. 2.

Actually, An eviction is a suit for possession of the property and in no way would an HOA has standing to sue for possession of your property 

I saw some of the properties with status "Occupied", "It's unlawful to disturb the current occupants" and "Buyer is responsible to obtain possession of the property" . 

The divorce gave your mother POSSESSION , but may or may not have also addressed OWNERSHIP.It also depends on the current type of deed recorded on the property.

(a) Upon termination of a rental agreement, a landlord shall return to the tenant the security deposit minus any amount applied to: (1) the payment of accrued rent; (2) the amount of damages that the landlord has suffered or will reasonably suffer by reason of the tenant's noncompliance with law or the rental agreement; and (3) unpaid utility or sewer charges that the tenant is obligated to pay under the rental agreement;all as itemized by the landlord with the amount due in a written notice that is delivered to the tenant not more than forty-five (45) days after termination of the rental agreement and delivery of possession.

Follow the procedure and take possession.