The prices are on the higher side deliberately. The best available quality was chosen. 5 billion is what Uhuru's sister - Nyokabi - was paid for 100 containers (see image below) and a number of other dubious contracts:
Nyokabi's Containers from China where she bought each for less than 200K including freight to Mombasa and charged The Sick 10, 000, 000 shillings[pdf]http://www.who.int/medical_devices/survey_resources/medical_devices_by_facility_provincial_hospitals_kenya.pdf[/pdf]