The Small buildings are
- Alchemy Lab
- Enchanter's Study
- Engineering Works
- Scribe's Office
- Salvage Yard
- Tailoring studio
- Jewelcrafting Gallery
- The Tannery
All of the profession buildings are small. Assigning followers to those buildings will give you access to the corresponding professions, even if you don't have those professions on your character. Note: Garrisons are character bound and phased for that character, like the current farm in Pandaria.
The Medium buildings are
- Pet Stable
- Trading Post
- Lumber Mill
- Inn: where you can pick up new followers
The large buildings are
- Mage tower
Buildings can be upgraded through several levels. You will be able to find blueprints out in the rest of the world which can be used to upgrade buildings. Buildings can also have specializations which can be changed according to your needs. Changing a specialization will probably come with a cost.
Followers can be assigned to buildings and tasks within those buildings. There are also missions that followers can be sent on. The UI is such that you select the activity, assign up to five followers and then select the mission from within that activity.
The mission activities are garrison specific content. Followers will not be completing quests for the player. The activities include:
- Quest: Used to level up followers, though high level quests have a chance to earn loot for your character
- Scenario: Takes longer than quests, but has a higher chance for loot
- Dungeon: Guaranteed to earn player loot, but take longer and are harder. Dungeons require five followers
- Raid: Raids take days to complete. They unlock when at least ten followers get to level 100. Transmog missions for lower raids will sometimes become available.
Garrisons will not include Dance Studios