Is there any specific area do you concentrate? 

Yea as good as mech engineering is, it can be quite unstable depending on what field you concentrate in...

I want to concentrate on working with investors.  

I am most likely going to be moving into the multi family sector with a concentration in value add opportunities until I can move to 100+ unit complexes and retire early from my day job.

I have noticed a concentration of seemingly successful Airbnb listings around Penn Station so I wonder if they are getting some people coming up and down the Amtrak corridor.

There has been some recent research about how new jobs are being concentrated in areas of existing jobs and the impact on real estate markets.Increasing population also seems to start a feedback loop of ever increasing values and investment.

I am a new investor & was wondering if it would be better for me to just concentrate on judgement liens properties, or do wholesale until I can build up some capital??

Instead consider concentrating on finding the following two kinds of living people, then making excellent business relationships with them:The RE agents that list the properties for sale on behalf of probate attorneys and professional probate fiduciaries, because attorneys and professional fiduciaries typically use the same 1-3 agents over and over again, andThe probate attorneys and professional fiduciaries that process probates.That is the bottleneck through which the properties in probate pass, if you can get in with those people you can offer them all cash on properties before they hit the market or at least hear about what is about to hit the market.Just one busy fiduciary or attorney could easily be doing hundreds of probates that include a year.Title co rep might be able to tell you who those people are, or you're going to have to see which agents are getting the listings historically. 

I am a part-time MBA student considering a Real Estate Evaluation and Analysis concentration and was looking for some pointers/advice.

What zip codes are you concentrating in?