I did look at the rental duplex--it looks in nice shape inside. I see the taxes are not insubstantial: Tax w/ Assessments: $3,744. ($312/mo) . So with maintainance and taxes you might be at 300-500 dollars a month before you have any money to put into a new mortgage.

I have owned two properties simultaneously and would not want to do it again--I guess I am low stress, and older than you guys. I would not want to endanger current property by taking out money on current home-- but I am very risk averse.

So I guess this might work for you if you wanted to go into the landlord business, but if you go into the landlord business, will you have to involve your current home? Will this make you stressed?

I think if I wanted to do the landlord thing, I would be attracted to a bigger duplex, with a larger half for me to live in. What goal do you think is more important--a larger living space for you guys, or being landlords? I totally understand the income stream idea, because I teach, too, and you are smart to be looking into other incomes!