My Dad likes to buy these types of properties and turn them into rentals to collect the extra cash flow from the non-conforming units ... double bonus if it is in an area with college rentals (that tend to rent by the room) or airbnb.

If you are wanting to be an absentee LL then you might  want to sell and buy a cash flowing property out of state (maybe Texas :)  ).    

I have found a four-plex that I think works out for my cash flow and CoC return desires, but I don't have 25% to put down, and don't know if I would qualify for a conventional loan even if I did. 

As I begin to build up I will use the BRRRR strategy to have significant cash flow.

You probably aren't cash-flowing $500 per month to break even ($500 * 36 = $18K profit + $12K principal pay-down = $30K = selling costs).

He's very pleased by the cash flow.

Make sure the numbers work-then it isnt so hard.One person here is buying negative cash flow HOPING for appreciation.......................lol. 

Not only should the rent from the main house cover the majority if not all of the rent, so you could live for free, but then when you move you can rent out the guesthouse that you were staying in also and have a Cash flowing duplex.

But aside from the bonus in cash flow that it will bring, I was curious to if the repairs and roof done to the garage will in fact add value to the property at all!?

Real estate goes through cycles of business flows.