Small scale distributor, would online platform business use it?

I was thinking of starting a small scale distributor business for a side business to help found my college and I am curious would any of you use it? From sending Invoice letters, thank you letters, appointment reminders, and other small letter type items, and maybe direct targeted advertising by mail. I was thinking of charging 2 dollars per letter up to 100 letters than doing bulk pricing after that. Is this a good cost and would you feel its worth to still send these items by mail?