What ID are you talking about? The ID associated to each home object and defined in [font=courier new]HomeObject[/font] super class or the catalog ID of furniture found also in [font=courier new]HomePieceOfFurniture[/font] instances?
Both can be found in [font=courier new]Home.xml[/font] entry found in a SH3D file (based on ZIP format). There’s no method to change the ID of an existing home object, but feel free to edit [font=courier new]Home.xml[/font] entry to change them. Just be sure to keep they are unique.