This is a life size guitar how much do I charge for something like this?[postimage id="5362" thumb="900"]

hundreds and hundreds of dollars

Oh it was my biggest cake I ever made and I charged $600 but I think it was too little.

me too but now you have a better understanding for next time

If you have read any of the other threads regarding pricing you would see it varies from region to region.  It is very hard to suggest pricing these days as ingredients and other expenses are soooo different from town to town, state to state and country to country!  How many servings did the final creation serve?  What do you charge per serving for wedding cakes?  That is a good place to start in guessing how much to charge.  Now figure out how much time you invested in it and it brings you a bit closer to the price you should have charged.

Great job and wow sooo big!!