Government-run national postal services are generally reliable across the region, and most post offices have dedicated parcel-packing services. For cash or more valuable items, it's better to use a trusted international courier company such as DHL or TNT.
There’s always an element of risk in sending parcels home by sea, though as a rule they eventually reach their destination. If it’s something of value, you’re better off mailing home your dirty clothes to make room in your luggage for precious keepsakes.
Poste restante is widely available (although infrequently used) and is the best way of receiving mail.