I can mark it up with a fee or by increasing the rate (or both, but I never do).

Your returns could be increased if you are willing to rent it by the room to individual students. 

I recognize this is not the sole source of return, but the other sources have their return increase with smaller equity position. 

For the next billing cycle they increased my charges by $500 and did not notify me of the upcoming charge.

The records of the closed title company MIGHT show how they handled the issue, but more likely they missed this issue otherwise as part of their solution a mortgage satisfaction document would have been recorded at that time. 4.

Ideally a HELOC is used for less then a  year project where you can refi or sell to pay back the HELOC. 5 years is a long time, things can happen and if you reduce the cashflow on both properties you'll be increasing the risk and having thinner margins.

Change all lighting to LEDTo increase revenue: 1.

- The increasing cost of damage repair and potential mold growth

Would this be an optimal win-win for risk reduction + tenant satisfaction?

However, if you're a W2 high income earner or business owner, I can't imagine it makes any sense to flip houses, mail mass post cards, wholesale, or build lead gen websites with the value of your time being better spent other places (such as learning about real estate and increasing your income through proven means), such as at your 9-5pm or growing your business, and your real estate is a long term process and you don't need "home run" deals to qualify or make it work.