The main (central) post office in Limassol and the tax office are located in the same building. The post office is situated on the ground floor with the entrance at the front. To collect parcels head for the long desk in front of you but not directly in front of the doors, to the right hand side.
The tax office is on the first floor with the entrance to the right of the building. The desk for handing in tax returns is located at the end of the corridor if you turn left as soon as you enter the tax office.
Parking is a nightmare so try to park on one of the side streets and walk there.