The dark times came to Vvanderfell. Vivec loses his power, Imperial Legion convened to Cyrodiil and forces of Dagoth Ur prepare to invade Morrowind. Make allies or deny them and keep going by yourself. You are Nerevarine. And the destiny of Morrowind is belong to you.
Here you can see some screen shots from Bal Isra.
As you know, in Chaos Heart you can get not only a manor, but a whole city. Size of your cities depends from your career in different organizations.
Firstly, you should get high ranks in your Great House. Then your patron in your Great House will allow you to build your own manor on your own land.
By the way, outpost of Bal Isra is already built at the beginning of the game. But it belongs to another member of House Redoran. If you join House Redoran the owner of Bal Isra will die (no-no, you won't be able to kill him).
Also, if you get the highest ranks in any organization, then you will see branches of your guilds in your city.