Our florist - a personal friend - operates her business in a different way: The client pays (wholesale) for the flowers & all the materials. For her fee, she requests a donation to be made to the Church to support her son's Ministry - a Mission in the Equadorian jungle.
I asked her what is the customary donation amount and she replied, "Whatever you think is fair.". I have no clue as to what would be considered "fair"! Any suggestions?