There is a possibility that I may have a "angel investor" who may not be a US citizen but would invest cash early on and therefore increase equity in the business.My question is which entity would be the "cleanest" for me to establish the business?

make sure they are a real business.. try to do business with a local lender who knows your market inside out... they will do a few things for you.1. establish long term relationship  HML from an owners side is about keeping great clients happy and repeat business.. so good borrower is just as important2. they know the area as well if not better than you will.. they will help keep you out of trouble or help guide you to the better deals as you run them by them.3. its always nice to walk in and talk with them in person...

Airy is a well established neighborhood.

I have some properties I manage myself that I have  owned in my name for over 20 years and others I do not manage myself vested in LLCs and corporations in order to establish a significant layer of protection.

The interest rate given to a private lender is usually established up front and the money is lent for a specified period of time, anywhere from six months to thirty years.Equity PartnershipsIf your investor client can’t finance a property on their own, a good solution can also be to use a partner who can make the deal happen.

I'm in the same boat although I have a bit more ($68K) to start out with in a newly established solo 401K.  

Absolutely, establish your screening criteria.  

When I work my farm area, I go back to the same properties regularly to establish rapport.Also, when dealing with pre-foreclosure, many borrowers (particularly with certain banks) are getting strung along with mortgage workouts.  

The value is established when you buy, then decreases with deprecation.  

Once renting isn't any cheaper than buying, and now that some time has gone by and people are re-establishing credit and getting scores up, they may move into becoming buyers again.