I am a conservative investor and don't like to take risks but like you, I live in the DC/MD area, and realized that in order to make some money, I'd have to look at other states, hence take some risks. I will just share my experiences to date.
I always meet up with the people I am planning on doing business with, because you get a good idea of how they run their business, look at their inventory, meet their staff, if any. You also get a feel of the area you will be investing in, sometimes it sounds a lot better on paper than when you are there in person. I rely a lot on my gut instinct as well, it has always served me well. For example, if a person claims they have so many deals but is unable to show you a single property when you make the trip there, there should be a red flag waving in your head.
I spent close to $10K in just traveling and paying fees for property tours (run out of Australia) I have traveled to North Dakota, Montana (saw the crazy rush with the oil boom and people sleeping in their cars) Michigan, Georgia, and Chicago. This was all over a period of 4 years. Hopefully you won't have to spend so much as I did, I was inexperienced back then. Still am, but now I hope I know a bit better!
Most of my contacts were from LinkedIn and various Australian Property Investment Magazines. This was before I knew about Bigger Pockets. Out of the many people I have met, and the many trips I took, I finally felt comfortable to go into a JV partnership with some one from Bigger Pockets. Don't feel pressured going into a relationship just because you made the trip out there.
It has been a learning experience for me because obviously, people have different working styles. Communication is key in building trust especially for the first few transactions. I suppose once you know the person well enough, you will not need that level of communication anymore.
The other thing that I looked for was how to exit a partnership if things don't work out. I do expect some repercussion but to what extent and is it reasonable?
Hope that was helpful, sorry if it was a bit long.