“Instead of fighting our way into Manhattan or South Beach or Hollywood, why not go into these markets where the product will stand out by its design and thoughtfulness?”

Major mechanical systems, etc.

Fantastic, love modular and adaptive designs.

I am a mechanical engineer, employed full time, with excellent credit score, so I'm thinking a low down payment FHA loan is a good option. 

No I do not use a spreadsheet per se as you posted, however, I do analyze each comp and adjust the value just as an appraiser would based on differentials in lot size, square footage, bed and bath counts, design and layout, condition, amenities, year built, etc.

Licensed especially for mechanical trades e.g. plumbers, electricians, HVAC.You have to start somewhere, your first one is a learning experience.  

@Robert Gunby, if you are referring to the EB-5 visa (immigrant investor) program, there are a few key parameters which need to be satisfied, namely $1mil or $500K (in designated areas) AND employment requirements.You can get more info at https://www.uscis.gov/working-united-states/perman...

So, looking for a new job, I have a friend who's willing to be a partner (but we haven't hatched out all the details yet), and interior design work.

No one will sell you a general liability policy for less than 10 times the insurance a PA contractor needs, so...As you can see, pretty much the whole Pennsylvania GC registration licensing system is all smoke and mirrors designed to give the public a cheap illusion of confidence in an army of bumbling handymen and to keep a second army of insurance industry lobbyists fat and happy.It's a bit different if you want an electrician's license for the city, and plumbing licenses, yeah, they're the real deal.There is absolutely no conflict between being a PA-registered or Pittsburgh-licensed GC and having a real estate license.

Make sure your mechanicals and structure are solid and then worry about the "cosmetics."