Others prefer individually picking vendors one at a time and building a more complex but also more specialized team.

I would prefer 4 doors in one property making $14,000 a month versus 20 doors with an average rent of $700 each (presumably across 5-10 separate properties).

That is the preferred method.

It can be set up as a trust allowing you to have checkbook control over your retirement funds.Second, location is of little importance here, this is a niche that not too many are familiar with, find a provider who offers great service and knowledgeable in this field, rather than looking for someone in your backyard. 

I live in Cary though so probably would prefer somewhere closer to Cary then Durham

This is true for the units where people will live in, kitchens are more of a capex cost but after you done you're units you have an idea of you're rental yield (preferably 1% per month) is and can accordingly decide the expenses.

That may be buying further education in the niche you want to pursue or use it to start doing deals.Hope this helps!

 $20 to $25 monthly insurance.Most investor prefer 30 years instead of 15 years mortgages to have more leverage.  

(I prefer Dallas over Austin right now).

I prefer RentecDirect as it is more user friendly in my opinion.