You have to be ultra careful because with this length of time holding the property a lot of things can go wrong and the market can change temporarily for the worst due to weather, holidays spike in interest rates, sudden oversupply etc...

She also has things like full time maintenance staff that make rehab ultra cheap for me.

Cash buying is not conservative, it is ultra conservative and produces very low returns.

Based on todays interest rates for every dollar of dead equity in a property you are losing 5% annually.Dead equity is the most ultra conservative approach to real estate investing and reduces your ROI to below the most conservative returnes.

I am not boasting/bragging but I am a bit offended that you would say such things to me when I seem to be having a nice measure of success in this business. 

You may want to reconsider your ultra conservative investment approach in order to grow and actually achieve positive cash flow.If you are buying homes worth 50K or less and renting for $850 + per month you are not doing as badly however you should try to find a way to pull all your dead equity especially before the markets turn and you end up losing it all.Paying off rental properties is not investing it is hoarding of cash and is extreamly expensive.Just food for thought

This is a tried and tested strategy that is widely used (and abused) in ultra-hot real estate markets (see: Toronto and Vancouver). 

We pride ourselves on their ultra-fast response time. 

Other more ultra conservative investors may differ so you must first decide if you are one of those or not.

I know, I take short 5 minute showers, and people at work boast about taking half an hour showers in the morning, which is why they're late.