There are 9 x buyers for owner occupied houses than there are investor buyers. 

They are all on separate parcels, paid off and occupied by long term tenants.

This vary heavily town to town. 20% down is great if buying strictly as investment but if you have a way of owner occupying I would explore that route and apply the 20% down to increasing value of property and instead using low money down loan. 

Owner occupied united increased by 8.4%"Still, although the overall share of households that rented decreased, the number of rented units increased by over a million units (43.3 million to 44.6 million)."

Local economies: Owner-occupied homes contribute to local economies.

How much longer will it take for her to finish he cleaning and painting to her liking, while your losing rental income on the other unit by her essentially occupying 2 units?

The triplex is occupied and currently bringing in positive cash flow.

Your answer needs to make sense, and be true.Also refi'ing your current primary into an investment loan also has the potential to be fraudulent if your family still occupies it as their primary. 

If you’re not occupying the property and plan to either sell it or keep it as a rental, you might want to consider a bridge loan through a hard money lender.

If anyone has an end lender that has successfully closed a handful occupied padsplit loans and can underwrite based off actual padsplit rents I would really appreciate an intro.