If I'm making my margins and getting the income I need to support a lifestyle, that's good enough for me.Again, purely my opinion.

We found this deal through pure luck.

Here are my typical requirements for a deal from a purely numerical perspective:Cash on cash: 7%+ average over 5 yearsAnnualized ROI: 25%+plus or minus depending on the location or other factors. 

If it is a pure investment, interest rate may be higher than 3%?

@Raj Gandhi The logic is smart, but doesn't work with a purely passive, single member LLC, rental business. 

Incredibly difficult to get off 0 as well, and the only way I did it was to finally convince my bank after a year to give me a loan purely to take me off 0 and even then it took a human underwriter to step in.

As an investment strategy however, buying investment properties, enjoying your 10-15% CAP and knowing that at anytime - 1 year or 10; the minimum will be breaking even on the sale, making your rental income pure profit for the duration of ownership.

No this is a purely hypothetical situation for me to practice the math and get some feedback. 

Solar powered with lithium battery bank for evening hours.

*I have since discovered that maybe the August v3 or Pro might be the way to go for a lock.I like the idea of z-wave or zigbee networks for these devices to reside on for battery efficiency and wi-fi traffic and a single point of control with something like the smartthings app, but I'm also aware that integrations can sometimes be messy and I may just need to download separate apps for the various devices.