There is a great book called "Deep Work" by Cal Newport which is all about staying focused amidst the distractions of modern life. 

Ordinary people can't afford to renovate their homes for modern living.

If any work, both materials and labor combined ,  valued at $500 and below, you do not need to have a license to preform the job. 

When you screen tenants you should be ensuring that their combined household income is at least 2-3x's your rent amount.

Zillow says both units combined rent for $1325, what are the rest of the numbers?

You've got the holy grail of a combination 121 primary residence exclusion and a 1031 exchange.

Up to 85% (or less) of Social Security feeds into taxable income based on combined income formula.  

Combine that with everything from the first BRRRR and the information begins to compound.

@Michael Gelatt I am giving these answers according to mortgage point of view, you have to contact your CPA for other concerns.1 You should be paying from your business account to keep it separate.2 You should combined both to cash out because you are refinancing any way. 

If this was my property in the price range your asking I'd take down the weird curtains, paint the  walls with a modern neutral color like a light gray or beige.