What I'm about to tell you is from my Architect's side.There was an article in Builder Mag a long time ago on this topic.  

I've never built more than two stories so perhaps there's a contractor on the forum that can give a more definitive answer...but in the discussions I've had with architects, engineers and contractors there doesn't seem to be a significant savings. 

What measures do you employ to mitigate unforeseen costly repairs, who do you include in your must come and inspect list (fire Marshall, roofer, architect, plumber, etc)? 

To do so I need an architect or engineer to draft up plans and calculations for the beam.

I'm pretty noob when it comes to architect the deal with anyone that is not a family member.

The architect got it designed and through the city without many hitches.

I noticed our General Liability policy has an exclusion for Engineers, Architects, and us if we fail to hire them.

I'd suggest that you talk to a home designer or better yet an architect.

With a good architect, engineer and expeditor, I imagine you could probably do it in a week with some hard work.Here's my thread:http://www.biggerpockets.com/forums/48/topics/90068-diary-of-a-new-construction-project

On the other hand my brother hired an architect a few years ago off there and I use her to this day!