I was in Guatemala and learned to my surprise that its national post has been disbanded. There's no functioning postal service of any kind, only private couriers.
How does that even work? By private couriers do you mean companies similar to UPS and FedEx? Or private couriers like the bike couriers in US cities? If I needed to mail documents to the other side of the country, for example, could I just drop it off at a storefront or would I have to hire one person to take the envelope the whole length of the journey?
The cartels could step in as a national postal carrier. Set postage agreements, and postage rates for garanteed services.
Not even FedEx, you literally hire a guy to deliver an envelope say from Guatemala City to Xela.