I've got my first "official" cake order for next Sunday (50th anniversary). I could not talk the couple out of a sheet cake, but did convince her to put a 6x6 floating tier above the 12x18 sheet for better presentation.
She has decided to go with 12x18, 2-layered spiced chai white cake with a cinnamon-hazelnut filling. The 6x6 square will be a chocolate rum cake with chocolate-raspberry ganache. BC icing and decorations. To feed 90 people.
I'm charging $2.50/pp, so the total will be $225. Does that sound fair to you?
Sounds fair to me. That's a large cake. Is it a "double-decker" sheet cake?
Yes. Two fully-baked 12x18 sheets, each torted and filled, for a total of 4 "layers".
In my proposal to her, I listed this pricing structure:
$2.00/pp for basic cake (white, chocolate), with BC filling and icing
$2.25/pp for speciality flavor cake, BC filling and icing
$2.50 for speciality cake with speciality filling, BC icing
She went with option #3.
Sounds "right on the money", and if she is willing to pay it, that's all that matters.
Post the picture when it's done!
Hola Meg! No dice talking them out of the sheet cake huh.. darn.. I was looking forward to icing some tiers with you too. 
I'd charge for more servings. According to my chart a double layer 12x18 will serve at least 100 wedding sized servings. And the flavors you are putting in would constitute a premium upcharge for me.. The rum cake and both the fillings.
The sheet cake would start at 2$ a serving.. with the filling it'd be 2.25 x 100 servings.. $225. The 6" would be 2$ a serving to start.. add the rum cake $2.50.. add the filling $2.75 x 14 serings.. $38.50.
how are you decorating it? Is it complicated?
I'd charge at least $260.
Sounds fair to me, sounds delicious too. Do you have those recipes, are they here on CC?
Let's see...
Spiced White Chai (tea) Cake:
someone posted in a thread here on CC. Plain white box mix, substituting equal amounts of strong chai tea for water
Chocolate Rum Cake:
found in Cake Doctor book
Chocolate-Raspberry Ganache:
2 cups whipping cream
3/4 cup raspberry preserves, de-seeded
1 pound bittersweet (not unsweetened) or semisweet chocolate, chopped
preparation
1/4 cup gold rum, optional
Combine cream, preserves, and rum in heavy large saucepan. Whisk over medium-high heat until preserves melts and mixture comes to boil. Add chocolate, remove from heat and whisk until chocolate melts and mixture is smooth. Refrigerate ganache just until thick enough to spread, whisking occasionally, about 1 hour 15 minutes.
(also works well with strawberry, omitting the rum)
Cinnamon Hazelnut Filling:
making this up as I go along 
1/2 cup butter (softened)
1/2 shortening
4 cups powdered sugar (sifted)
1/4 cup cinnamon hazelnut coffee creamer
½ cup toasted hazelnuts, finely chopped
1/2-1 teaspoon cinnamon
Cream butter and shortening; add in sugar and remaining ingredients.
With your price break down.. it sounds good.. I didn't notice the chai part of that first one so that'd change my price a bit too.. they'd be the same price per serving.. $2.75/serving and 114 servings.. $313.50 which I'd probaby round down to 300$.
http://forum.cakecentral.com/modules/Forums/files/cake_serving_guide_219.pdf
This is the chart I go by..
how are you decorating it? Is it complicated?
Awww shoot! Forgot about that part .
Not quite sure what I'm doing yet; but you can help me torte and fill layers, right ?
Reminds me that I need to start doing som RC flowers this week. Loverly .
Hi missmeg, It is not fair. Do the math.
12 x 18 = 216 inches, divide by 2 = 108 servings.
Now, 6 x 6 = 36 inches, divide by 2 = 18 servings. A wedding cake serving is 1 by 2 inches, and normally 4 inches tall. Sheet cakes and square cakes are easy to figure out.
You are selling 144 servings for the price of 90. That is not fair.
Cakes are priced at the number of servings, not by the amount of guest.
Check the Wilton site, get a wilton yearbook or get a serving chart from someone's site. I know you said you are new. If you are going to charge for your cakes then you need to know what they serve. You cost yourself a lot of money. $2.50 times 90 = $225/ $2.50 times 144 = $360. You lost $135.
I hope this helps you. I had to learn this a long time ago. CindiM
Hi missmeg, It is not fair. Do the math.
12 x 18 = 216 inches, divide by 2 = 108 servings.
Now, 6 x 6 = 36 inches, divide by 2 = 18 servings. A wedding cake serving is 1 by 2 inches, and normally 4 inches tall. Sheet cakes and square cakes are easy to figure out.
You are selling 144 servings for the price of 90. That is not fair.
Cakes are priced at the number of servings, not by the amount of guest.
Check the Wilton site, get a wilton yearbook or get a serving chart from someone's site. I know you said you are new. If you are going to charge for your cakes then you need to know what they serve. You cost yourself a lot of money. $2.50 times 90 = $225/ $2.50 times 144 = $360. You lost $135.
I hope this helps you. I had to learn this a long time ago.
CindiM
You're right, and I figured that out after chatting with Jeanne on the phone .
Using the largest party serving size recommendation from Wilton (and then still taking a small discount), I came up with 108 servings, for a total invoice of $270. The client said they would mail me the check this week, along with directions to the event.
Thankfully the clients are aquaintenances at church, and me and my family are also guests at the anniversary party, so I'm not concerned about the check .
Thanks everyone. I really appreciate the input you gave. I do have to remember that it's the number of SERVINGS the cake provides, not the number of guests at the event :doh:.
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