Our Art Centre adds metal strapping to bark paintings for hanging. Also some artworks are repaired or a base is put on a carving that doesn't stand up properly, etc. We would like to add the cost of these 'value added' to the price of the art work, but not have it as part of the artists account. Not exactly how to do it but maybe a field in the initial catalogue area. Value added - Description - Cost. This cost then gets added to the price. Maybe it needs to be free of any Markup percentages.