Honestly I never thought I would get this many diverse answers!

This will help you gain an investor's perspective and will introduce you to a diverse amount of strategies that exist in real estate. 

Could you pick a county with more diverse munis?

So a balanced portfolio is a nice option here, in doesn't have to be sell all SFRs and go full bore into MF either, keeping a balanced, diverse portfolio to give you options as your investment career continues to grow / evolve.Dave

I would want you to be in a populated City that has diversity in economics and population growth.  

Indy, Milwaukee, Memphis or any other 2nd or 3rd tier city with diverse employment.Pick one and spend a month looking at everything on sale there to get a feel for where and what you want to invest in.Then spend another month becoming an expert in your selected market, again by looking at absolutely everything.After two months you'll know a deal when you see one.

There are a limited number of small multi family units available.Cleveland heights has some 40,000 some thousand people as well but it is widely diverse from the border of East Cleveland (a low value urban area) where the residents go to that poorly performing school district to high end "mansions" in a couple neighborhoods. 

An upcoming public hearing on Monday 6/5/2017 @ City Hall Rm 400 1pm testimonies being heard.item 170519  An Ordinance amending Chapter 19-1300 of the philadelphia code, entitle REAL ESTATE TAXES by creating a tax foreclosure diversion program that requires housing counseling assistance, updating tax installment agreement payments to help taxpayers with financial hardships, and other related items; all under certain terms and conditions.show up and voice your opinions, give your support(I can't imagine who wouldn't support this).

LLC is superior for RE because you separate yourself from the property: i.e. no personal liability...but an S-Corp allows access to your personal assets...bad idea...if you like the structure of an S-Corp, you can have your LLC taxed as an S-Corp...they are pretty diverse...typically more affordable as well.

The #1 thing I look at when evaluating markets is jobs and job diversity.