You don't seem like the right kind of buyer for this property because you're looking to rent and positive cash flow. I don't know if you're aware but this building is under rent control and the 2nd unit's $1,900 rent cannot be raised much and there are tight restrictions on removing the tenant.
The type of buyers this property is perfect for are two separate parties (think friends or siblings) buying it as a TIC with each party occupying one unit. The existing tenant will be kicked out using OMI (Owner Move In), assuming the tenant is not protected. Then they do a quick conversion to condos in two years and raises the property value.
Such buyers are most likely buying on emotions because they are purely looking for a nice home to live (not cash flow), possibly buying in that location because of proximity to family or about to start a family, etc; so they will pay top dollar. I've seen it happen too often - investors using brains are no match for home buyers using hearts.
At any rate, there is no reason for you to rehab the tenant-occupied unit beyond basic liveable condition since the rent will be low.
I don't see how it makes sense for a lone investor. For a single party, the only way it'd make sense is if you fall in love with the house and must have it.
With that said, I can see it going for north of $1,400,000.