Townhouse Development Cost - S. Seattle

[Scott Christopher]

I've got a 22,000 SF property in S. Seattle / Skyway with existing rental. Options to develop it include a 14 unit apt building, or 8 townhomes, or simply put 4 townhomes behind existing home.  The property is relatively flat, no critical areas, the architect and King County seem to think its pretty straight forward.

I've heard on the more affordable side townhomes can be developed for around $100-$125/SF.  I'm trying to understand the other typical costs, in particular dirt work, etc., to better understand overall budget  Also looking for a good, affordable builder and/or architect for a project like this.  Any insights from the BP community would be appreciated!