how much can i charge for fruit cakes.... from 6" an above.? covered in marzipan and sugarpaste. pls someone give me an idea. Thanks

AHow much do you spend on ingredients for a 6"? How many hours does it take you start-to-finish to make one? How much do you pay for overhead (license fees, insurance, etc.)?

You really need to figure costs.  Fruitcake, if done well(or why do it)  uses expensive ingredients, requires attention weekly with good brandy or spirits, and takes a lot of time.  A thumbnail sketch has these starting at about $30 a pound.  That is about half the size of an 8" loaf.  You might be able to shave some costs on a larger cake.

Really nail down your costs or you will lose your shirt here.