It's now produces about $450/mo in cash flow after all expenses, not including debt paydown.

It will not produce as many results with such a narrow target property, but it is another method to generate potential deals.

I have a particular case where all the investor has to do is pay 50k on a house that needs no work and is producing 5k per year return. 

I’m considering keeping it to do short term rental and producing some cash flow while paying off the rest of the loan.

Their first round effort has produced $42K in 0% funds to use over the next year and I am going to use those to accelerate my purchases and re-selling activity.

I recommend putting that in to some type of investment account producing dividends and other long term growth vehicles.

One of these opportunities I have been considering is investing in businesses like laundromats, as they supposedly can produce substantial cash flows (according to an investor I’ve spoken).

Most home inspectors can turn-around and produce a report in about 24-48 hours after the inspection. 

The additional income from the ADUs will easily cover the cost of the loan and produce really solid cashflow.

This property has actually produced positive rent growth over the same period.