But what makes it most appealing is the low cost of the property + great cash flow all paid up front.

REI appeals to me for the purposes of wealth acquisition, self sufficiency and earning more from my money.

Fortunately, we were able to appeal and finally get a lower tax assessment for 2019.  

Your only remedy is to appeal and spend thousands and thousands in legal fees.I'm limited in what I can say since this case has been going on for 3 years and isn't over, but a judge signed off on cancelling a foreclosure auction that sold to a 3rd party bidder, 6 months after the sale proceeds had been disbursed.

Before the appeal, taxes were $2350 and we got them down to $1700. 

Personally working on the upper unit as you can see here:https://youtu.be/2-iutfXnUxMand here: https://www.lizsoucieloans.com/blog-1/newfloorsnw2...Had to appeal some conditions in the basement for ceiling heights in order to proceed with permits (2-4 week delay) and additionally have to install fire sprinklers throughout the entire building..... 

Though paying off your mortgage can make you a pretty high priority target, you can conceal that through the strategy of equity stripping - essentially making a loan to yourself so the property does not look so appealing.

Brick has good curb appeal and generally won't look run down, so from an outsider perspective just looking at the street on Google Maps, it looks pretty good.

Even if it does not impact the price directly, it is more appealing specially if the tenant been there for some time. 

What about it is more appealing than something more passive such as mutual funds?