I started reselling rackspace email service a few months ago, and just now I got a bomb dropped in my email:

As of November 1, 2017, your account will now have a $150.00 per month minimum commitment. This means that if the dollar value of the Cloud Office products that you are using is greater than your $150.00 per month minimum commitment, then there will be no change to the amount that you are invoiced unless you add more products to your account. Otherwise, if the total value of products on your account falls below the minimum monthly commitment, you will be invoiced $150.00.

So minimum price of a service could change like that without notification? It seems quite harsh - as when I joined this is not what I signed up for. Now I have a month to transfer everything I have somewhere else or pay the extra fee. I offer email hosting for my client who host a website with me, so it's not that easy to grow my email client base that fast!