All prices dependent on house size and location.

small house (1 room)
 _
|_|

medium house (2 rooms)
 _ _
|_|_|

large house (4 rooms)
 _ _ _
|_|_|_|
  |_|

mage tower (5 rooms: multi-level)
         _
        |_|
     _ _/
    |_|_|
 _ _/
|_|_|

5 room cross
           ___
          |   |
          | 2 |
          |___|
            |
   ___     _|_     ___
  |   |   |   |   |   |
  | 5 |---| 1 |---| 3 |
  |___|   |___|   |___|
            |
           _|_
          |   |
          | 4 |
          |___|

4 room square
   ___     ___
  |   |   |   |
  | 1 |---| 2 |
  |___|   |___|
    |       |
   _|_     _|_
  |   |   |   |
  | 3 |---| 4 |
  |___|   |___|

3 room tower
4 room tower
5 room tower

Note that you can simulate basements with towers:
         _
        |_|   is the same 
        |_|   tower as      _
 _ _ _ _|_|_        _ _ _ _|_|_
|_|_|_|_|_|_|      |_|_|_|_|_|_|  <-- ground level
                           |_|
                           |_|

small house (1 room)

medium house (2 rooms)

 North-South        East-West
     ___           ___     ___
    |   |         |   |   |   |
    | 1 |         | 1 |---| 2 |
    |___|         |___|   |___|
      |
     _|_
    |   |
    | 2 |
    |___|

large house - south-facing
large house - east-facing
large house - north-facing
large house - west-facing

each with 4 rooms. south-facing example:
   ___     ___     ___
  |   |   |   |   |   |
  | 4 |---| 1 |---| 2 |
  |___|   |___|   |___|
            |
           _|_
          |   |
          | 3 |
          |___|