I was faced with the same option, I choose to stick to about a dozen investors, a few with very, very deep pockets and use no more than 3 on any project, usually any one could swing 90% of what went on alone,  much easier life getting started that way. :) 

I tend to think more investors would choose Moody Analytics over census to analyze investments but to each his own no probs.

As a foreign investor, how do you choose the area in America where you want to invest?

@Jason Cook Any particular reason you are choosing DC?  

Sometimes the path we choose does not end up being what we thought it would be.

An umbrella policy can go for a few hundred dollars for $1MM or more.I usually choose a higher deductable policy since when you get a lot of properties your insurance costs really start adding up.  

like @Bob Bowling said, location is crucial, if you can get near an area that's very desirable (beach, downtown, area with lots of jobs, etc) you can expect to have multiple renters to choose from and expect appreciation of the property.

You will find amazing opportunities if you choose to invest in US.  

Nothing says the seller has to take any offer, they can choose to accept whatever offer they want.  

This deal is a lot smaller than I wanted but I need to be picky with my numbers and the properties I choose.