Re: Replacement costs for next doors retaining wall › Flat Chat Strata Forum › Common Property › Replacement costs for next doors retaining wall › Current Page 10/06/2016 at 9:56 pm #25010 Sir HumphreyStrataguru If it is effectively the fence on the boundary, then I would say it is a shared responsibility. It sounds like it is retaining your property as much as it is protecting their property.