i'd start light, then adjust once you see what you need, but here goes:Turbo: (0) unless you have a HA issue, then (1).
bumblebee: (0) these are predatory whelks and will eat your beneficial microfauna.
Margarita: (0) these are temperate species that will die soon in warmer water.
Nassarius: (2-3)
Astrea, Trochus, Nerite, Cerith: (3 each)
run with that, and see which snails you like and which ones work the best for your particular setup. you can always adjust after that. stocking lightly means that your CUC won't starve back to the proper levels, which is what happens if you overstock.
HTH