I always assumed there was something really wrong with that house since it's pretty cheap and it won't sell.

Those doors and trim that look good enough to keep when you first walk through a property in bad shape will look pretty rough once everything else around them is new and/or freshly painted.  

What you just described is pretty typical with these guys.

Early retirement has been one of my goals since I began working and I initially decided to do it through mutual fund investing since that seemed to be a pretty safe choice.

If it’s a condo, they’re usually pretty easy, older homes have problems, but depending on how you’ve got it set up, you may not run into an issue for months, so paying someone $$$ for nothing kills me. 

HD has the grip strip ones for $1.79 sq/ft and has pretty good reviews.

Petersburg for pretty much my entire life.

The first red flag is that 20k is a small amount and the uses are pretty limited in a big market like Dallas.  

Sure maybe you break even on your mortgage but that’s a pretty risky appreciation game to play.

That is pretty lean to say the least.