Focus on factors you can know (laws, economic trends), insure against those you can't control (i.e. floods, fires, earthquakes, etc), and have large reserves and a good exit strategy if things change, making the investment no longer desirable. 

Here's some quick info that might help clarify how rental income is taxed: Real Estate 101: How Rental Properties Are TaxedIt probably also wouldn't hurt to sit down with your tax professional and have him/her give you some expert advice specific to your unique tax situation.

Closer to Boston still sees more resilience in recession / economic downturn.

@Korey Enstad, as with the others, I am not a building inspector or fire code expert. 

You need to become an expert in your market and the business. 

My take on the broader situation tends to fluctuate but I believe class C/D investing in Baltimore City if done in a targeted, professional, and consistent way is a giant economic opportunity.

I'm no lender or borrowing expert, but would think both parties sign for the whole loan, like a husband and wife do.

For some reason, property managers who have stayed in the business for the long hall are pretty good at "qualifying/assessing" a tenant's character and are experts at separating the sketchy ones from the great ones

He is an expert in explaining how to use LLCs.

Wildlife expert inspected to find out where they were getting in.