BUT if you are keeping the units for rentals, and have a hot water BOILER, by all means keep the radiators/baseboards that go with it, install a combi boiler (Navien or similar) that combines hot water for heating with hot water for showering.

Anyway, house hacking is beneficial because it combines multiple benefits in one.

Or some combination of both?

I would move on.The only time this even remotely makes sense if you can buy the unit next to yours with the possibility of one day making a great combination, or you buy them in bulk and play the numbers game with a very long time horizon.

Taxes and insurance are usually less than 2K for the year combined, Maintenance is a function of the quality of the property but is typically like 5-10% of rents. 

I imagine starting out I'll need to use a combination of hard money and a pool of funds from multiple friends and relatives. 

Combining posts like this with podcasts like yours and others is helping me to think bigger (and scarier) about my goals.

The kitchen was moved downstairs, the smallest master bedroom upstairs was expanded to a spacious one, combined with the other bedroom.

Regardless it is getting easier and more cost effective to submeter with modern technology so I think you will see more and more landlords going in that direction.

This combined with the very favorable seller carry terms make my spidey senses tingle.