The possibility of value add due to the previous owner taking care of it but not raising rents or renovating.

That's why the FHA 203K and FannieMae HomeStyle renovation loans are so popular.

About 2 of the units in each property have been renovated, leaving 6 units needing to be updated as tenants leave.

In 2014, I bought a 3 Family Brownstone for $900k, renovated it for $375k.

Well, hmmm, my contractor starts Tuesday on the renovation process.  

The kitchen will be fully renovated and opening up to the dining area with updated flooring and lighting.

I purchased my first duplex in 2016 for $65K and put around $50K in renovations. 

Are you interested in renovating / managing rental properties?

However, your desire to renovate, or the current owner's desire to sell the property, does not supersede the tenants' rights under the lease agreement, and you inherit the terms of that lease when you buy the property.If the lease does not include the use of the basement and the garage, the owner (or you after you close) can petition the tenants to remove all of their belongings from those areas, but the tenant would presumably have the right to comply and thereby not compromise their continued rights to the first floor (basically, a lease violation that is curable, if cured, is no longer grounds for eviction). 

You need to be able to buy and renovate for 65-70% of market value.