If I find a deal on an area I would consider living when I move back I would like to be able to pull the trigger and possibly refinance into an owner-occupier loan once I move back to the US.  

MOST people regardless if they are renters or home owners spend over 30% of their income on housing and utilities. 

Agreed on spending money, I would be asking the owner to purchase all of the smart locks himself as an investment into the property. 

They can be a very valuable resource when deciding if a property is a good investment or not.  

In 2019, I launched my own revenue management agency to help Airbnb owners boost their income and achieve greater returns on their short-term rental properties.

If you do decide to help them out and rent continues to be late simply have a talk wiht them and remind them that rent helps pay your bills and since you did them a solid ask for the same in return.  

When you get an owner that replies, FOLLOW UP.  

I am also versed in Novations, and owner financing.

I'm a central CT based investor, flipper, and property management company owner. 

If this is for a residential 1-4 unit non owner occ / investment property I would compare a few different lenders.