One tip regarding "spaceholders". If you are creating property names in AutoCAD Architecture (ACA) and ever intend to use the same names for Revit Parameters do not use "-" as a replacement for spaces. Use CamelCase or undersore "_" instead.
"Room-Area" will be fine in ACA
"Room-Height" will be fine in ACA
Room-Area x Room-Height = Room-Volume will work fine in ACA too ie 10x5=50
In Revit "Room-Area" will read as "Room minus Area" and the "formula" will error as there is no Room or Area parameter (unless by chance there is for some other reason. Revit is a bit thick at interpreting parameter names
Room_Area or RoomArea will work in both