In business, the simple way to get rid of problem customers and maybe to avoid taking them on in the first place, is to ensure you have per customer pricing and

In business, the simple way to get rid of problem customers and maybe to avoid taking them on in the first place, is to ensure you have per customer pricing and agreements. For example, client A is a good customer, so a support ticket for them costs just $150, but client B is a right royal pain in the backside and so their support ticket cost is $550. Similar scaling for development etc. Keep raising prices till they go or stop calling so much, as required.