Your site averages 36 visitor traffic per month & you have 21 backlinks.

Which state may be suitable to invest the LOC?

Sell or purchase with contingencies that require the buyer/seller to cooperate with your search for a suitable replacement or to wait for your sales before scheduling closing.   

My options are: 1) to post a "three-day notice to perform or quit", 2) write her to indicate the lease violation and allow her to break the lease now to find another suitable apartment.

They may demand more time to find suitable housing then he is maybe forced to renew?

The public is welcome to come to any of our meetings as a visitor, membership isn't required. 

I think I can find some in the $35-$45k range and Craigslist indicates that rent would be in the $700-$900 range.One thing that I seem to struggle with is in drawing the line between what's suitable for a rental vs what I would personally want.

Here are some elements of security to consider;  Building Entry Doors Access Systems - How do visitors notify tenants that they are at the entry door?

It sounds like you bought a property that definitely isn't up to code, and not suitable for renters (dirt floor?). 

But if he is seeking companionship or more, it may be a good idea for you to send someone else to his apt when he requests a visit, or communicate via text or better yet a message system.