I think you can only work with a fixed set of parameters and properties in the Expression Editor.
That said, if you would make a list of 'element' costs properties for m1, m2, m3, piece etc, in theory you would be able to make schedules with costs if you fill out those fields in ArchiCAD.
However I find it quicker to fill out the quantities in Excel, derived from a well set up schedule, since there still are quite a few things that need to be taken in to consideration for costs, that make little sense to model.
One way or the other, you are inputting data / numbers in to a field of text/data. Favourites would streamline some of this, but in practice during design, things get changed around quite a bit, and whatever was put there from a favourite settings (cost per m2 or such) will likely have changed by the time you get to the cost calculation phase.
While it is possible to get data in to an object from a text file or such, I think this method is a bit crude, but maybe someone with more experience can help out here.
Going back and forth between excel and archicad schedule with Properties is working quite fast, unless you are trying to import back a spreadsheet with a few hundred fields of properties.
Erwin Edel, Project Lead, Leloup Architecten
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