If they were within your lease you could have sent them a default letter, explaining what they needed to do cure it, copied SEC 8.  

The longer you wait to address this the harder it will be to deal with.I would send a 14 day notice to cure and not bother knocking on doors.

The home would have to be cured back to be used as a residence and this would cost the lender money. 

Neighbor (N) gave notice, you cured. 

However, if I talk to them and they don't fix it or they actively avoid me, the next month I mail and post on their door the same letter with the appropriate eviction or termination notice with the opportunity to cure the problem.

The cure to both - the 4 ions: education, action, progress(ion), not perfection".

The cure to both - the 4 ions: education, action, progress(ion), not perfection".

The seven day notice is more properly called a "Seven Day Notice of Default and Opportunity to Cure." 

When you issued the NTQ (Notice to Quit), was your intention is for the tenant to cure his situation by paying rent and continuing tenancy, or was your intention to try to force the tenant to move out.

If not cured, property code permits breaking the lease, but you must move out.