In 2008, while spending a few months in Mazatlán hiding from the winter cold, we were excited to receive a letter for our landlord from Baker University, Kansas with some great auxiliary markings. Upon his return, our landlord shared our enthusiasm and generously gave it to usr.
October 14, 2008: The letter entered the mailstream franked with a 42c first class domestic meter.
It was then handstamped on the reverse with the pointing hand handstamp, 'Returned to Sender - ADDITIONAL POSTAGE REQUIRED FOR MAILING INTERNATIONAL AIR MAIL.'
The zip code of 91912-5501 pertains to Chula Vista, CA, where our landlord used to live. The "código postal" for Playa Sur in Mazatlán is 82040.
A routing barcode was sprayed on the back of the envelope at some stage.
October 16, 2008: An additional meter was added, franked with 30c extra to pay a total of 72c per ounce international treaty letter rate to Mexico.
October 22, 2008: The letter was then backstamped with an in-transit wavy line machine cancel of Ciudad Benito Juarez, where it crossed the border.
October 27, 2008: It was backstamped with a Mazatlan receiving CDS.
We were one of the few residents to have a mailbox which was actually used for letters. It was a typical small upright metal box, with padlock, and not very secure. In fact, I think I saw the letter sticking out near the top and wiggled it out to save getting the key.
Our landlord assured us that it contained an invitation to the Fall Convocation. As he is unlikely to ever update the código postal, this will continue to happen to the letters to him from Baker University!
The front of the letter has a rough black 6-bar and pink pictorial cancel commemorating "Día del Cartero" on 12 November. It shows a map of Mexico and a mailman walking with his mailbag.
Our mailman (cartero) wore the hot pink and lime green uniform of the Correos de México, newly launched that September. He rode a bicycle and blew his whistle to let you know he had delivered a letter.
On the Día del Cartero he lingered after blowing his whistle, waiting for a tip which should be between $20 pesos and $50 pesos, depending on how much mail you get. This is his reward for the good service he has provided you with during the year - and hopefully the next!
Bills such as electricity or water were shoved through the bars of the garage by employees of the respective companies, and were likely to be blown into the street if you didn't retrieve them promptly. Ditto with copious quantities of junk mail, which was mostly advertising.
(This cover was written up in the July 2009 issue (Vol. VI, No. 3, p8) of Auxiliary Markings, the quarterly journal of the Auxiliary Markings Club. It was also written up in the March 2014 issue of The Album Page, the monthly newsletter of the Oregon Stamp Society. As well, it has been written up as a one-page display which may be shown at PIPEX 2014. I am getting a lot of mileage out of this cover!)