There is a company in my area that it looks like it will cost me about $400 a year per property but after this week I would welcome that "insurance" as I just had a large unexpected AC bill.  

Would you be better putting the $100k in the stock market, or in a treasury bill at 4% or do private lending at 10-12%? 

What I do for my units with shared meters is I charge 50% flat to each tenant which prevents waste I get no issues with any waste due to this but the ones that share electric bills do get many complaints due to the size of the bill.

Possible.It's not only about paying your bills.

.: I just got billed $365 by my property manager for replacing a toilet fill valve and supply line.

What are some pros that I can highlight from the seller’s perspective.Here are a few that I’ve come up with:1) monthly income at a higher interest rate;2) avoiding a larger tax bill by reducing the purchase price (on paper);3) a promissory note that they could potentially sell down the road.Any other major ones I am missing?

Look at T-bills vs hard money loans for extremes in rates and risk factors. 

Water bill triples so they want to check for leaks, too many cars parked in the street. 

The language is still in the state bill where a city can deem an unpermitted unit "unsafe" or "substandard" - therefore no tenant can legally live there.

Air conditioned air leaking to crawlspace making crawlspace heat or cold depending on season causing more power bill to tenants.