I did send him a formal email on the returned check.

There is no formal arrangement and the tenant and the deal was done on a handshake.

Tax appraised value was lower than what I paid so no way was I going to volunteerly disclose my sales price if they can't figure it out.Mass appraisal process is different than individual bank appraisal process so that can create discrepancies.Some people protest through a formal protest process which can work to lower values.So just lots and lots of variables....good bad and otherwise.

Will I need to get a formal "home inspection" (which seems prudent), what should I do specifically with relation to my new mobile home?  

Do I formally fire them or do I just find someone new and now I have two people in Area A.

The way I see it, I spent a significant amount of money on my formal education, where not only did I "work for free", but I paid for the privilege.

I'm inclined to provide her with a formal letter ending her month-to-month agreement and letting her know she is being asked to leave so that she cannot stretch the date out longer or claim that she gave notice when she was actually asked to leave.  

Some states make you put them into trust accounts, and you may be required to formally inform your tenant of its location, and/or send them yearly interest.

This will require a more formal procedure in evaluating applicants.  

Just send a formal looking letter or email telling them they are going to have to start paying their own utilities when they sign a new lease.