In addition you can concentrate on areas that have capitals or universities/large colleges, (government & education can weather economic storms well).

In fact Nashville is one of the areas that I will be concentrating on for buy n holds.

I am also getting a certification in Financial Modeling and Valuation Analysis with concentration in Real Estate.

Then concentrate on finding victims

If your properties are concentrated in one area or state you could be facing the rebuilding costs for multiple locations and the loss of rents for those same properties all at the same time.You may want to have your agent look into a policy on all the properties with a very high deductible and see how that cost would impact your plans. 

Visiting 5 schools in TN in January, and wanted to see if any brokers/realtors that concentrate on student housing were open to meet.

I concentrate on getting in and out forcing appreciation when it make sense, then selling ASAP. 

The value of SFHs is driven by home buyers, as a investor you should be concentrating on multi units where th evalue is driven by investors.

It'll allow you exposure to good returns on real estate while freeing your time to concentrate on generating higher income to invest in more properties down the road. 

Smaller multi-family in Atlanta is very concentrated.