Once you place an order we set your project up in our production system. We will send you an Order Review to look over and approve before we start manufacturing. It is your responsibility to ensure all the sizes and details provided are correct. If there is a discrepancy please let us know at this time. If you need to add or subtract a door, this would be the time to do so. If you add a door we will send you an invoice for it through our online payment system Stripe. There are no refunds for doors you have already paid for.