Its not used because, and at least from my limit experience, I've never come across two investment that had such similar characteristic that I needed to get that level of precision in my measurement.

Are you planning to flip or buy and hold, from my limited understanding Auckland can be rough for the latter. 

I reckon you've got the right idea in looking for financial independence, but, are you likely to get any lifestyle independence any time soon?

I just want to automate routine AirBnb message traffic so I can limit the amount of time that I'm on my phone during the day while still keep customers happy (VRBO / Homeaway don't seem to need instant responses in my area).  

My knowledge of them is limited so I can't speak to their business model.

I've only begun within the last 5 years, and capital is limited. 

I've learned a ton from her posts here on BP and have called her to pick her brain on market rents in specific areas I'm not as familiar with and have limited MLS rental data in Orlando.

Live cheaply and don't let lifestyle creep set in.

If you are going into the space with limited experience, do you think that using other peoples money is a good idea?

This means no limits to the number of 30 yr loans.