Price Per SQ FT for New Construction in the SF Bay Area

I am considering a potential SPEC house build and I was wondering what the going price per SQ FT is for new construction in the SF Bay Area. New construction would be medium to high end. 

I have talked to a few GC's and the quotes I got were $140 sq ft for lower end and $240 - $350 sq ft for mid to higher end. 

Has anyone recently built new construction and have any insights?

Thanks.