The price is reasonable.

There are eventually going to be implementation costs. Sometimes you're required to have custom code developments there, so that has to be part of the implementation price. 

The initial setup of the tenant is a big cost element of the service and we were doing multiple tenants for our customer. Given that structure, the costs for building additional tenants seemed exorbitant given that the business rules and portal setup work effort was very easy after the initial setup. CA should price additional tenants much less than the first tenant for a single customer.