Is it a 9 x 13? If so, I would charge at least $35 (but I would NOT star tip the whole thing...looking at that much star tipping makes my hands ache!)
Of course, pricing most times depends on your demographics...
It all depends on the size of the cake and how many serving you can get out of it.
I don't do sheet cakes, but I agree with msauer, maybe $50.
I think (if I''m remembering correctly) that a 9x13 yields 25 servings. So if you did $2/slice that would be $50.
Duplicate post, please also see: