Originally Posted by
Poganin
There are main quest-lines in each zone, yes, and when you pick a building for your Garrison, the quests associated with it are part of the side-quests in that zone. If you and your friend pick different buildings, some of your side-quests will be different while others may overlap. You can still adventure together and help each other out, though. because no matter where you are in Draenor, there will be lots of points-of-interest (treasure, rare spawns, bonus objectives) you both can encounter.
Translation:
Yes, you won't be able to quest together if you pick different buildings. But hey, look, there's a rare! Kill it, quick!
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