Tricky question! Our housing market is comprised of single family homes, condominiums, co-ops and TICs within 10 very unique districts. Within each district are another handful of subdistricts. Offering an average price per square foot for all of San Francisco is as challenging as giving the average temperature of the US, if that makes sense?
Here is a district map to help narrow your question and would be a little easier over the phone. http://www.sfarmls.com/docs/areamaps.htm