Tampa has amazing growth potential and have personally witnessed @Josh Green work miracles for his clients.

Treating people like people doesn't mean you make the relationship personal as Nathan suggests and not all tenants will screw you over whenever it suits them.

I'm sure there are great, stable areas in Columbus but I'm not convinced the appreciation has been as strong as most would lead you to believe.I don't know much about Cincinnati, but one glance at the median list price over the past 5 years (attached below) would be enough for me to write it off as not appreciating.I'm personally partial to Detroit and that's where I invest and do a lot of business with other folks as well.

Personally, I've been in the mobile home investing niche since 2007.

Given the details you provided, I personally might not want to settle this in mediation with this tenant however as I'd probably just want a judge to cut through the BS and tell them to pay up and get out at this point.

Since your a hands on person and have contractor contacts.  

They are basically the same as applicant number one except there is an opportunity for them to make more money with the second person if they chose to work which means higher probability you will get paid on time. 

You should get these things for all applicants:1. rental application with employment reference and personal reference2. credit3. past landlord reference4. check for eviction historyMost apps like RentSpree include all this in what the tenant pays to send you a report.I cosigned for my daughter and her boyfriend on their first lease.

It should go away.If it's only them smoking and a personal issue, I would reconsider dropping this if they are otherwise good tenants.

Hire a company/person that is solely a QI like @Dave Foster they do it every day and will keep you legal and on track.