My preference is to have the tenants pay their own heat, especially if there are already separate utilities and/or furnaces.Another down side locally is if you rent to Dept. of Social Services tenants, the formula they use to calculate rent gets thrown off if heat is included in the rent.

Social Security numbers and credit checks are not needed until after a showing and the applicant decides they would like to continue with the application process.

Other than that its really just overcoming any of the strange obstacles you might encounter along the way.

What are the obstacles you've encountered?

Any niche depends on your market, learn the market, understand what can be done, then learn to adapt strategies that solve the problem.All real estate sales is about solving a problem, it might be the turning of inventory of a 5 billion dollar portfolio for liquidity or it could be selling some little old ladies home with her moving to a nursing home.Most all the investor residential deals will be about solving some problem, real estate is a very social business, it's not like Ford moving units off an assembly line out to dealers, it's an in your face, personal problem solving transaction every time, an individual seller always has a goal and a problem getting there. 

I plan to add more to my portfolio in the future - the biggest obstacle for me is diversifying projects in my area.  

I am most certainly not immune to these, however I consider things that involve finances to be a rational endeavor, and so my autopilot social responses would not affect the bottom line of a business negotiation.

That being the case it is your responsibility to drive the transaction and remove as many obstacles as you can.

social media?  

We have to overcome any obstacles or objections for prospective purchasers and create desire to own.Obstacles to buying may include - not enough money to buy, no finance available, not familiar with the area, can't travel to see the land and the area and lack of information.