I checked a few pages of messages and the walkthrough and I haven't seen anything about how to get into this building. It's the one between the Monastery and Arnika. You examine the door and it's locked from the inside. You can see in the windows on the second floor, but I can't seem to find a way in. What am I missing?

You cannot get into this building right away. There is a way inside the building, but you will find it later in the game.

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Inside the building is a teleporter to the Umpani area. While you are exploring Mt. Gigas you can find the teleporter to the building and open it up. You can then use the building and the teleporter any time you want. There is another builing like this south of Arnika on the way to Trynton that has the T'Rang teleportor.

Good Luck,
Knarflling

You won't find a way in until later in the game... you will one day be able to transport in.

Thanks Knarfling!