Being able to distinguish between what I know, and what I think I know. 

@Cristopher Andrade take a look at the Hospitality Guide from The Distinguished Guest.

Those who don't distinguish between "good" debt and "bad" debt just want to get out from under it.

Unless you are in the city, it can still be difficult to distinguish the "up-and-coming" streets from the "do-not-touch" streets, and they are often right next to each other.

Then it had to be a master's because everyone gets bachelor's degrees, now everyone goes for masters so I know people in their 30s going for PhDs to further distinguish themselves.

This area is distinguished by smaller "cookie cutter" homes, some under 1000 square feet with 2-3 beds/1 bath with few frills.

The more you learn in regards to real estate; the easier it will become to distinguish which niche suits you and what to do.If you have time consider spending 30 minutes for 30 consecutive days on Bigger Pockets.

Its important to distinguish between the gross income DSCR the OP is posting about and your SBA 1.35x DSCR, thats a true DSCR commercial calculation based on property annual gross income - annual operating expenses = net operating income (NOI) annual / debt service annual payment = needs to be 1.35X or higher to qualify.

Do something 100 or a 1000 times in an area and you likely know where the true limits of safety and legality are, but it’s often hard to distinguish that expert knowledge from careless attitude going in and a new investor puts themselves at everyone’s mercy by doing so