Places like Maplewood, Richmond Heights, Affton, etc. would be where I would start (if looking at long term rentals).

I used expeditors for specific projects in NYC, but in Long Island, I hired an architect who's also an expeditor, where I bough a SFH, the previous owner done unpermitted work.

Long term rentals are tough but maybe you could try looking into STR.

I usually avoid such youtubers but I am also seeing there are lot of houses sitting in the market for a very long time and the builders inventory is also rising and at some point, they will have reduce the pricess massively. .

If it breaks when someone is in there, what is the rental income you would lose and how long would it take?

I would say it depends on if the property is a pain and what your long term goals are.

Read your insurance policy before making a claim as I think most do not cover long-term damage especially if it could be easily found and mitigated.

The repair costs will take multiple years to recoup and with the age of the property I'm concerned if it's even worth holding long term or get out while I can before I fall into a money pit and get stuck.  

I would buy another property before I would pay down debt, as long as my rentals are saving money for themselves.

Something you might want to consider is what is it going to cost you in the long run if you're doing your own books?