Similarly, if you put several Class D tenants in a Class A 4-plex, what do you think will happen to the property?

The #1 determinant is the Tenant Pool.If you don't believe us, try putting several Class D tenants in Class A apartment buildings and watch what happens.

Similarly, if you put several Class D tenants in a Class A 4-plex, what do you think will happen to the property?

-----------------------------------------------------------------------------------------------------------Recommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

I have no idea why folks spend a ton of hard earned money on these "guru"  classes.

They invest only in Class A or B properties in good markets, where it’s easier to find good agents, good management and good tenants. 

Alternatively the other side of the city (Pikesville, Towson outskirts) still decent rentals but they are farther from employment centers.

They are very real and, very C-D class. 

@David YoungRecommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

Multifamily real estate has traditionally been a stable asset class, and the Washington D.C. metro has traditionally been a stable market area, making the two together a good safe bet, especially for anyone with a long-term view of their investing strategy.