Luckily I did charge additional security deposit because there were a few red flags in their credit history.

My natural instinct sends up red flags.

so much so that many contractors use red wood 2x4's as plates for walls being installed directly on concrete, particularly if the concrete is directly on the ground or in a basement. 

Red flag! 

It doesn't seem to matter if there is yellow or red across a major nearby street, all that matters is if the street where the property is located is green...it has proven to be the number one indicator for buying a drama free property!!

Yellow letters with handwritten font and handwritten address on the envelope in red ink.

One red flag is taxes seem low - are you counting city, school & county?

One of our biggest "walk away" red flags during customer interviews is a customer who wants to play GC.

I forgot to add she was debating the pet deposit and that should have been a huge red flag.  

Hi Zach,The Columbus market is red hot right now.