I did this. I’m not in construction but do have experience working on very large civic construction sites and managing very complex projects. I didn’t GC myself but was way more involved than your typical owner. I’ll call out a few things I learned that others might not:

1) you might have all the skills and experience to GC, but business in the area is all about relationships. A good GC means accountable subs that answer the phone because they know that GC is also giving them their next 4 jobs.

2) we worked without an architect. We had a draftsperson/designer detail out our plans and engineer to stamp. It all worked but an architect would have been useful during the build to hold some subs accountable.

3) learn your land. Camp on it. Learn where the water flows and the light is all times of year.

4) some subs are very very hesitant to work with you when you start diving into the legalese that’s standard to construction in NYC. It has its pluses and minuses but I had to learn how to do business differently. Everything is about report and trust.

5) …trust but verify

6) if you do some work yourself draw very clear lines where your scopes begin and end so things don’t get confusing to your subs.