Another is because when a landlord accepts rent late, his behavior effectively changes the due date.  

I would be worried that this would be discriminatory behavior, but it is probably OK since it is focused on the income.  

Because of that past behavior, they know how to play the game better now. 

Why else would would you attempt to justify such bad behavior?

Thankfully I haven't had to go to the parents for payments, occasionally I have had the help of a parent with student behavior.

But, with this tenant, if they know they're supposed to call you first, and they aren't, you need to stop this bullying behavior. 

Their behavior does sound suspicious.

That type of behavior should be discouraged and she should be penalized financially.

This information is available free of charge on the internet at the following sites:Sex Offenders: www.txdps.state.tx.usSan Antonio Area Crime Stats:http://www.neighborhoodscout.com/tx/san-antonio/crime/REASONS FOR DENIAL OF APPLICATIONSIf you failed to give proper notice when vacating a property.If previous landlord(s) would be unwilling to rent to you again for reasons pertaining to your behavior or that of any family member, guest (welcome or not), your pets, or any animal on the property during your tenancy.If you have had three or more late payments of rent within the last 12 months.If you have an unpaid collection filed against you by a Property Management Company.If an unlawful detainer action or eviction has occurred within the past five (5) years.If you have recently received 3-day notice to vacate.If you have had two (2) or more NSF checks within the last 12 monthsIf you have filed for bankruptcy or foreclosure within the past 24 months we may deny your application.Any bankruptcy must have been discharged at least one year previous to the date of your application.If you have allowed any person(s), not on the lease, to reside on the premises.If we are unable to verify your information, we must deny the application.No Businesses may be operated from the property.

This tenant was absolutely horrible - in both their communication style and behavior.