I was going to make some cake dummies for display and was looking for some tips... I want to make some cakes with fondant and some with buttercream. Should I use royal icing where on a real cake I would use buttercream? And I don't have too much space to store them, some might end up in a display window, will that be a problem? Thanks in advance for answering my endless questions 
Donna
Fondant will hold up and harden for safer storage. You won't want to use buttercream. Royal will work, though it may yellow over time. you can also use spackle-it can be sanded smooth. You can also buy a product called perma-ice. It looks similar to buttercream, but hardens.
I know its not the most popular, but I use permaice as a base for my dummies (love its durability), and royal and fondant for the decorations. When I want to change decorations I just stick the dummies under water, wash off, and start over.
If you use permaice, add some water to it for easier smoothing. It dries quickly so you need to work fast. 
I use (all crisco) buttercream all the time on my dummies. They hold up just fine. Ironically, when I put this icing on my cakes, it's great, but when I put it on dummies, it hardens as hard as concrete and will keep forever. After 8 months or so, you could "kinda" see a yellowing start to show up. Of the last 30 pics posted on CC, 11 of them are dummies made with BC and are sitting on display right now. I don't wrap or treat the dummie with anything .... BC straight on the styrofoams. When I'm ready to change the decor, I just run a knife under the icing and it pops right off. Less than 5 minutes and I'm ready to re-decorate.
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