Hello SoCalGIS.

It's been a while since there have been any posts in here, so I'll go ahead and start another.

I have a question regarding the general cost of building footprints.  Does anyone know what to expect in terms of per footprint cost from a consultant when digitizing footprints (roofprints is probably a more accurate term) from aerials?  Here's a little more detail:  It is expected that the digitizing be done at a 1" = 100' scale.  Footprints should capture the corner architecture of the structure.

Also, what about estimating how many footprints to expect?  I used a simple formula where I looked at Assessor information and zoning designations to guess how many in Palmdale(see below). 

         *~42,000 developed parcels 

           ~36,000 residential homes
                      x 1 structure per parcel average +
           ~6,000 other developed parcels           
                      x 3 structures per parcel average +
           38 schools           
                      x 12 structures per parcel average +
           ~1,800 mobile homes                 ========================                  
~56,300 (round up) = ~57,000

Anyone have a formula they used before?  Is there a standard out there?

Thanks for your time.

Marc Zuber
City of Palmdale, GIS Specialist
661 267 5354