Here's the model I'm proposing.
1. Set a designated enclosed area for LAN, hardware cost: US$200 for the wired router and cables for 20 users.
2. The enclosing the area will cost about US$6,000
3. In order for someone to enter the room, they need to pay (say) US$10 per person until they leave the designated area. If you want to re-enter, even after going for a bathroom break, tough, that's another US$10.
Virtually no maintenance whatsoever. Smart City is required to pay a certain percentage in order to do business within Disney property.
The above will work because I have setup several data-cafes overseas this way.