Floorplan Courtesy of: The Mage Tower.
Cost:433,200 GP
Floors:3 + Roof
Max. Items:2119
Max. Lockdowns:2119
Max. Secure Containers:15
Image Scale:1:2
This building is quite large, and has plenty of room for an entire Guild.
The addition of a useable roof makes this building quite unique.
It's one shortcoming is that from outside, you can see into Floor 3 if you stand under one of the Roof Supports (seen on the Third Floor Image).

Outside / Roof:

First Floor:

Second Floor:

Third Floor: