However it has had issues with settlement.

@Robert Fountain if your agent did turn in the contract right away, then it is really the selling agent that is the issue. 

Receiving a call or letter, I would have corrected the issue.

It's not a problem with the concept of building a 2-4 unit property, the issue is all about the large capitalized expense costs vs. benefits.

Since septic systems are rated by bedrooms, there should be no capacity issue that you would run into.  

I left out the important details about how much work the house needs: new windows, roof, no AC, not even a fume hood in the kitchen, sometimes mold issues in the basement, broken windows, landscaping. we basically self manage which is at times frustrating.

Overseas you have currency exchange rates timing and other issues.

Credit and down payment are not an issue and I am pre-approved for financing.)

I would bet that a recorded lien would cloud the title to the point that a title company would not issue title insurance on the property without a lien release. 

I don't need the cash flow so putting it towards the mortgage isn't an issue for me.