There is some updates that need to be taken care of like flooring and paint to get top value based on other sales in the neighborhood in the 170-175k range.

You invest under your own name and carry sufficient insurance.

I've gotten several quotes ranging from $2k-6k a year. 

Our total capital contributions over the 20 years would be about $2.6m.So my first question is, can you find businesses (like apartment buildings) in the $800k-$1m price range that cash flow $24k per year after debt service and > $120k per year after the debt is gone?

Since a 3/2 can differ in value from one neighborhood to the next, I'll give a range of value depending on upgrades and small differences.

Edit: PITI on the house can range from $600-1500.

Not sure if I am calculating those numbers correctly but the rental comps are within that price range.

I would not ever dream of doing this .especially in this price range

Both small units have wall HVACs (Is that sufficient for heating/cooling?)

An HVAC system that provides sufficient air movement is your best bet, especially with a dehumidifier built in.