Mind you, I'm born and raised in Elizabeth, and I know for a fact the vast majority of duplexes in North Elizabeth have a basement or attic apartment, or both.

When you do is th ecash flow sufficient to justify holding.

There are a very few people who are able to do that, but the vast majority get demoralized if they follow this thought path. 

I doubt there's a sufficient energy savings or a real increase in the ability to heat a space.If you already have electric baseboard then I would just leave it.

(Run away unless there is a compelling reason to expect improvement)Is income steady to rising, and sufficient to pay the rent? 

If you don't have sufficient emergency cash reserves, you can find yourself in some trouble.

A simple painters caulk or window / door caulk is not sufficient for any thing in a bathroom.

The vast majority of insurance people out there do not understand this because the majority of them are not active investors themselves and because of this, provide incorrect information and either inferior products and in many cases, based on my experience, the absolutely incorrect product altogether.

We want to be sure we have sufficient options for backing out if necessary. 

I would strongly suggest acquiring knowledge from a vast array of sources (also I suggest researching in full the resources and the potential agendas there of) .