The 1% rule is a cash flow negative deal in my area, so I would probably want to be all in at less than $140k, which means my offer would be $110-115k

LoopNet usually has a few.

These are usually 20 and 30 something year old's and I highly doubt they own the homes free and clear that they are offering as owner-finance.

I just want to fully understand why their net income was so negative on this report.

I think it could take less than a year but folks usually think they can do this in 2-4 weeks and are disappointed;-)I'd see what's been done similar to your project in the last two years and check with those contractors, & developers for hard numbers, then meet with the Building Department and Neighbors.

The calculator shows a negative $300 flow.

The benefit you get in cash flow is usually the smallest of the returns from investing in real estate.  

Remember when you have only 2 units there is usually not much margin to handle vacancy or damage.

To properly evict you have to give them usually 30+ days notice, though most courts I have seen say its a 60+ day.

There’s a meet up usually monthly for folks of all experience.