What is the actual charge to buy a number?

In this article:

You are looking to purchase a telephone number and you want to know what fees you will be charged. For any number purchase you will see a one-time set up fee and this cost will vary.

In addition you are required to select a plan. If you are planning to immediately port out, select the Port Away plan -- otherwise, you can consider another plan based on the functionality you seek. You will be charged monthly for this plan as long as your number is with NumberBarn.

Regarding the cost of a number, here are a couple of other articles you might find helpful:

I'm porting away. Do I need to select a monthly plan?

What taxes and fees am I subject to?