Right now you can build for around $150 a sq ft, per my contractor without anything fancy. It can go all the way up to $300-400 a sq ft if you want high end stuff.
If you need an honest contractor, call PJ Rielly at 415-317-3731. If he gives you a bid, he will stand behind it. Whoever you choose to do the job, never pay any contractor in full until the job is finished.
Dave Tap Tapper