There are some rough areas crime wise, and there is an area that you'll want to avoid affected by the "Collesium Plume" chemical spill area. 

No harm there.The other buyer's initial attempts at financing fell through and so I came in with the same offer but much more solid terms (BIG earnest $ amt and no financing contingency) and so the seller dropped guy #1 after the due date was reached and signed my offer.I have the money to buy it all cash, but I really don't want to.  

Try googling the term "house hacking" and you will understand.I meant no harm and sincerely do hope you use the resources on BP to better yourself and your investing career.

This outgass chemicals can cause headache, vomiting taking forever to get rid of it.

We don’t know any PMCs to recommend in the area mentioned, but since selecting the wrong PMC is usually more harmful than selecting a bad tenant, you might want to read our series about “How to Screen a PMC Better than a Tenant”:https://www.biggerpockets.com/member-blogs/3094/91877-how-to-screen-a-pmc-better-than-a-tenant-part-1-services-and-processesWe recommend you get management contracts from several PMCs and compare the services they cover and, more importantly, what they each DO NOT cover.

He may come back to harm her.

If you put in your lease agreement there may be issues with the windows, and how the tenants can avoid harm you should be covered legally but you should replace the windows overtime.

The difference with Pit Bull is their strength, which gives them ability to do more harm.

I would send a letter focusing on the nuisance it is causing others and harming their equal enjoyment of their home. 

In relation to harming my bottom line,  I have been at this for a very long time managing my own so I pretty much know what I´m doing.