Oh I see, yes I agree that in general if you are going to sell cakes you should already have a firm pricing guide to go by. Otherwise you will always second guess yourself, and IMO, if you don't know what you need to charge it will leave the door open for negotiators, cheapies, want something for nothings, and other garden variety cake snakes. That being said, I think the newbies ( I am one) will always need a little reinforcement from time to time, until they get their big girl cake panties on and cultivate the confidence to charge exactly what they need to.
Regarding the 10-8-6 serving 74.....yes you are correct, Wilton says so. But I usually go by a different serving chart, one that is more "party sized" servings, which is about 50-51 generous serving. But that's just me, I am a skinny fatgirl who believes in enjoying a big piece of cake and not just a taste.