No home: Players have to walk to access most features. Shops are placed around the world. Emulating runescape's NPC spawns. More of a remakish server.
Small home: All resources such as npcs, useful objects, and bank, are in one small specific or closed off area. Everything is accessed by teleport. An example of this would be underground in the Mage Training Arena. Usually has skilling areas.
Big home: The "using an entire city" concept. NPC spawns are placed around the city. The city's bank buildings are used as the banks. Objects are spread around the home. Most skills can be completed right outside the city, such as fishing, woodcutting, ect.