UPS ******ion with overcharges #UPS

#UPS seems to be running an ******ion business in South Africa.Ordered two small items online.Get a call from G Khumalo saying I need to pay their customs clearance,brokerage fees etc The amount was way more than expected,but before paying it I tried numerous times to contact G Khumalo but did not succeed.I wanted to query any further hidden costs .I hesitantly paid the invoice.Today #UPS delivery arrives with a NEW invoice for more than the previous one.More import duty,more brokerage fees... I refused.If Amazon and Aramex can tell you upfront at the time of purchasing items,what the customs duties will be ,then so does UPS know !