I've never used a cake dummy. I've had a few 2 tier wedding cakes lately that would have been much nicer had they had a third tier. How do you charge for a decorated cake dummy?
well, since the major cost of a cake it in the time it takes to decorate it. Many dummy tiers don't cost much less then to make that layer out of real cake. It would cost just about as much as a real layer of cake.
If your cakes involve a lot of handwork, or intricate piping, then the cost is really on the outside of the cake.
The point is dummies take the same amount of work to decorate so price accordingly.
Dummies = 90% of the cost of real cake. The styro costs about the same as the cake. The icing and decorating are the same. All you're not doing is filling.
This has been a hot topic on here before, but most agree that a dummy should cost close to or the same amount as a cake. You are still taking the time to decorate, so price accordingly!