Is there any method or best practice to calculate the size a sinking fund should be? My estate is made up of new build semi-d and detached houses with a central green area, street lighting and ~2000m2 of public roadway, drainage etc.. We currently have a very small sinking fund as we are a new OMC. Is there a way to calculate how much we should be adding to it every year? We dont have really costly things like lifts etc. but I imagine long term maintenance could add up quickly.