If the proforma has the rent roll at $1400 a month, there is a discrepancy that could lead you into a bad assumption on your business plan.Also one caveat, be aware of physical delineations around the area like bridges or railroad tracks or a canal. 

What we really need is a single internet "bad tenant" list to warn each other.

But he has a bad credit and cannot qualify for a $200k loan to buy it.

Yes, there are many out there that do it and nothing bad has ever happened, and I say kudos to that, I just would never do that.

Is it okay to file an extension or a bad idea? 

They know they ins and outs of their property, and you bad-mouthing the property isn’t going to going to endear you to the seller.

It's pretty tough to find a quality carpenter as well.

I don't see that the rate of bad behavior is higher among voucher residents.  

Quote from @Isla Arshad: You know in your heart she's a bad tenant.

You may not get the same tourist volume as Pigeon Forge, but you’ll attract a more consistent, quality guest base.If you're leaning toward an MTR, healthcare contracts and university housing demand will give you a steady stream of tenants.