Red flags to be aware of: Are there any deal-breakers or warning signs I should be looking out for in the listings or during the initial research phase?

Account Closed In my experience, once you get burned a few times as a landlord, you develop your own "deal breaker" rules that you stick with as a policy. 

People know there credit is shot and wont even apply knowing 620 is a deal breaker.  

Account ClosedThis all happened early on this year in January, but I was reminded about it last week  when I woke up freezing haha....I had a pipe in as basement burst above my breaker panels and another pipe in a bathroom at a house that flooded two floors.

looking for some insight on selecting my next tenant...I'm doing my applications through Cozy and I've used a lot of the guidelines I've learned about on BP...just trying to figure out my "deal breakers"House is up for $1675/month which according to all my research is just a tick below market....I posted on all the normal sites and have had a TON of inquiries...like 60+ contacts.... 2 open houses with 14 groups actually showing up...... but only 3 submitted applications.

That would definitely be a deal breaker. 

Not only is it a good idea to show where the water shut offs are (at least behind the toilets due to the concern about clogs) but also where the breaker box is.Very recently we had an incident where, on a Sunday (of course; all disasters happen on a holiday or a weekend) the tenant was running the dishwasher when it suddenly started smoking, popping and burning. 

Since it''s nationwide they could cherry pick the most friendly district/circuit to file in.

However, I still don't know what he did besides add a master switch to the breaker box and cap off a junction box.

It can/will be the ice breaker or deal ender for what you’re looking for.