It's probably because I'm new, but I thought staying away from places with only one industry, high crime, and low income was the rule of thumb.What am I missing? 

Does this mean they're technically violating lending rules/regulations by not informing the lender that the property will be sourced as a rent-by-the-room asset? 

Any rule of thumb to use while analyzing?

I invest in a couple states and I also am a agent in new jersey. my rule of thumb for a client is when they say I'm hoping for in a sentence describing a property I dive a little deeper into there goals because it sounds like they are trying to fit a square block into a round whole.

They will know setback rules, road widths required, easement documentation for road and utilities, postal box and bus stop.  

If you refinance too soon after your 1031 exchange, the IRS could see it as a way to sidestep the rules and potentially tax it.

One of my clients recently purchased a 4/2 single family house that was positive cash flowing, hit the 1% rule, and was able to execute a full cash out refinance so it was a clean BRRRR!

I suggest you understand the 50% rule.  

Let me know if this would pass any primary residence rules since I won't be living there, but he will.

I will be really interested to see what stance BP rules committee takes.