My hubby's buddy who owns a gym bussiness is having a Christmas party  and wants m to make him a cake for the party. I have no idea how much to ask. But here are a few things the cake will have: 3d rice krispie treat tree, big fondant bow around the cake, snowmen, little cakes decorated tolook like presents, an ice rink made out of sugar. Oh the tree will have actually christmas lights thanks to battery operated lights. Yes he will know not to serve the tree.

I do this for more as a hobby so I am not looking to really make any money on it. I just dont want to lose money. 

If I posted this in the wrong spot so so very sorry

"I do this for more as a hobby so I am not looking to really make any money on it. I just dont want to lose money. "

Does that include labor?  How big is this cake? 

You can compare to other local custom bakeries to price out. Understand that making a $1,000 cake for $200 still seems like a "rip off" to someone who doesn't understand the work involved. Buddy may be looking at Costco's $70 sheet cakes and thinking THAT'S A LOT OF $$$$$. 

I would calculate # of servings and figure $1/ serving as cost, depending on how much you hand make. Fondant, krispies, etc. I would probably to say to Buddy, that will take me 4 days to sculpt and make, will serve ______ people. Most bakeries would charge about $________ but I'll do it for $________.  If he doesn't fall over at that point, you may have something to talk about.

Even as a "hobby", I would write something down. "White cake, buttercream icing, fondant accents, serves _____ delivered and set up at ____pm on ________. $ ______ due 3 weeks prior.

Heck, I even have my kids sign IOUs. No mistakes, no misunderstandings--- you know?