"I think 8 is too many -to prep at the place."
Not necessarily true, depends on what apps. The more critical number is how many total.
You store em in bulk back there, then transfer em to trays as needed.
There are other factors. Like time of day....if this is close to meal time and no meal is being
served, just your apps, then I think 1 app of each x 5 isnt enough. (and isnt anyway, IMO)
Also, people's "taking" habits differ when they're being offered a tray on the fly than when theyre
"looking over" the entire say, app buffet before selecting. And a "2-buck" app cant be very filling
(if it is youre gonna lose your tush on the deal)
We do app events, open buffet style often. 100 people avg. 8 to 10 choices, and guests consume one
or two of each, with average being 7 to 10 apps each. And that's not even when theyre hungry.
With 5 you have even less choices--that will work against you if youre not careful.
I would either stick to the 5 and make 40 to 50 percent more apps, or go back to the 8
figuring 1.2 of each.
On the other hand, if your CLIENT is specifying how many apps total, well that's different--
then theyre the ones limiting portions (or running out early) not you.
As to your price per person, as SG said we'd need to know what goodies you had in mind.