We don't have a backed player guide for Project Zomboid yet. How many can play depends on mods, world and play style. The price follows memory, not player count.
Set up your server for Project Zomboid
The console runs in your browser, and you edit files there or over SFTP. Values such as player count or world name are fields, depending on the game.
Main menu → Join, then enter address and port, 16261 by default. Each player picks a username and password on their first visit; those only work on this one server.
How do Workshop mods get onto the server?
Each mod needs two lines in servertest.ini: its Workshop ID under WorkshopItems and its mod ID under Mods. Maps also go under Map. Players download the mods automatically when they join.