Additionally, research the local market dynamics, economic indicators, and property management options to ensure you're making an informed decision.It's also a good idea to consult with local real estate professionals, property managers, and investors who have firsthand knowledge of the market and can provide valuable insights and guidance.

We either make improvements to the property, add money to the 3 month reserve account if theres any gaps or add it to the cash flow for the year.  

Additionally, since this project is already in flight, you run the risk of mechanic liens taking priority over your loan as they can backdate the lien to when work commenced. 

Have you investigated whether zoning allows you to add an additional unit to your property?

I'm looking at flood zones, population growth/decline, crime rate, the economic trends and future or current incentives for development in the area, what the biggest employers are, Zillow for rental comparisons, and property pricing.

@Dave FosterThank you for contributing additional information regarding DSTs and 1031s.

Require that they name you as an additional insured on their poliyc2.

For pre screening are you simply looking at income, debts, employment etc? 

However your situation becomes a trickier case study since these properties first served as your primary residence which could provide additional benefits form a tax perspective not available to an owner of investment real estate and nobody has a crystal ball and knows the property with certainty will transition into an investment property. 

Additionally, I introduce myself to the neighbors within 2-3 houses and explain what I'm doing.