We are looking at a site for development that is 30 acres, the seller put a small oil pump jack that is 15' high.

My advice on situations like this if you are a small fish stay in your own back yard plenty of good deals .That way you can keep track of all the stuff that needs your attention fill in the blank ___.BIG fish well the whole  USA can be played they have the team in place to do a long distance rent ,rehab etc...

I live in Midland TX which is dominated by the oil and gas industry and contemplated on purchasing a house or building a duplex to rent to a oilfield company.

A lot more sharks than fish out there 

The scammer then ask me if I'll pay him a few hundred to go away, but I told them, shouldn't done that before you got the lawyer, but you now have to deal with insurance.My wife had a younger sister killed by an oil company truck of a major oil company running a red light.

@Nicholas AiolaAre there any real estate crowdfunding platforms that allow you to deduct your investment against active income (similar to oil/gas)?

Expect to fish. 

With $600k, I'd be more interested in gas and oil mineral rights and/or a syndication.

That's certainly worth something though it doesn't enter into any IRR calculation.A successful fish store in the neighborhood had to move across the street.

Fish is scarce on the market.