The problem with that set of formulas is that a fixed rate loan will NEVER have different monthly payments due (your example starts at $675, then $674.25, etc.).  

This coming year set the goal of getting more committed to learn and expand my knowledge to avoid previous mistakes taken as well as to be able to effectively continue to expand my portfolio.I’m here to connect with others who are also passionate about real estate, and I’m eager to learn from your experiences, insights, and advice.

•Set up notifications when a listing matches my criteria.Has anyone built or tried something similar?

I wonder if the change of density could off-set cost of underground enough to make it make sense.... 

I believe they are expressing their displeasure with the fact that I have not accommodated some of their recent requests that went far beyond the scope of what is required (like insisting a licensed electrician switch out a smoke detector when we could do it ourselves) and I had to set some boundaries after years of high maintenance for them.

It never hurts to have an additional set of eyes to look after your property.

Also look into whether the city has already set up regulations around STR or whether there are potential changes coming down the line. 

Provided you are sticking to the letter and spirity of your rental agreement, you have to set boundaries People that get indignant over you setting boundaries are not worth worried about. 

What sets your lisitng apart?

You know how to manage a property.To get started, your first steps should be getting licensed then meeting with a local RE attorney so they can help you get set up with your contracts, management and lease agreements, etc.