I ran a BBS from 1982 to 1986, on an Atari 130xe computer with several floppy drives. Ultimately the system had four drives and had an average of around 30 calls per day on its single phone line. The board was called "The Ritz Hotel".
It started out at 300 baud. I remember purchasing a 1200 baud SmarTeam modem for a couple hundred dollars for the board. Somewhere along the way, I bought a Hayes 2400 Smartmodem and that's what it ran on for its final year. I took the board down when I went to college.