Although I'm an architect, I'm having a bit of trouble wrapping my head around the code requirements for live / work, especially in terms of HVAC (can we use the ceiling hung heaters or do we need new residential HVAC systems?)

As a point of comparison, I spoke with an architect as well, and his all-in estimate of design plus construction was not too far off of the design/build quotes.The kitchen would be brand new (it doesn't currently exist). 

When starting a real estate development company, should you hire the head architect and civil engineer, etc or should you hire them per project as contractors?

It's not that easy unfortunately.I have had an expensive topographic survey done, however my Architect and Surveyor struggle to provide the total square footage.

From the Biz Journal:'UC Berkeley's Terner Center for Housing Innovation surveyed developers, contractors, architects and nonprofits building market-rate and affordable residential projects on why costs are so high.

I ask because the realtor wife saw some drawings I provided her husband (a contractor) and said she would love to be able to give her customers something like this, but architects are too costly.  

It's not until after you've spent dollars on architects and lawyers that you get to the commission vote. 

Right now you've architected a nice shiny building...that doesn't have a foundation. 

I am looking for a Professional Engineers (P.E.) and Registered Architects (R.A.). to draw some plumbing plans to convert a one family heat system to two.

I am an architect whom lives and practices out of Westchester County.