This topic assumes that you have read the How to Find Items topic, have located the items you want to buy and entered the store that has those items.
Item Availability:
When you enter a store, the available quantity of each item is displayed "as is" at the time you entered the store. It is possible that during the time you are adding items into your cart or checking out, someone else might have already bought these items.

If one or more items are not available or the quantity is no longer current at the time the order is submitted, BrickLink will show you those items, delete them from your shopping cart and give you an option to either resubmit the order or abandon your shopping cart. If the grand total does not meet the store minimum buy amount after this has happened, you will be only given an option to abandon your shopping cart or add more items to your shopping cart.

Global Cart and Store Cart:
There are two visible carts when visiting a store on BrickLink. The green cart within the store is a store-specific cart (a summary of items added within the store), and the one in the top navigation is the global cart (a summary of all items added to various store carts).

Submitting an Order:
After you registered or logged in at Checkout, you can select how you want to pay for your order, how you want your order to be shipped, whether or not you want your order to be insured and also enter any additional comments for the seller. When you're ready to submit an order, press the "Submit Order" button on the bottom of the page. For information on how to add items to your order after submitting it, see section below.

Please remember that submitting an order is a contract. Please submit an order only if you're serious about buying all of the items in that order. By submitting an order, you will enter into a legally binding contract to purchase all items in that order from the seller. Please also read the seller's terms and conditions before submitting the order. These vary from store to store and it is important that you understand them. If you have questions which are not answered there, please contact the seller before placing your order. You can also click on the "Store Terms" tab at any time prior to checkout to view the seller's terms & conditions.

After you submitted the order, you will receive a confirmation e-mail notifying you of the order. If you did not receive an e-mail confirmation, you can check if the order was properly submitted by going to your Orders Placed page. If your order was successfully submitted, you should see it listed there.

Adding to an Existing Order:
If you have recently ordered from a store and the order hasn't been marked as paid, packed or shipped yet, the system will add to that order instead of letting you place a new one. That order had to be placed in the store you are buying from now. The following conditions must be true for an order addition to take place:
  1. Order Status must be Pending, Updated, Processing or Ready
  2. Order Payment status can be any except Completed
If the store has a minimum order amount, you do not need to reach that amount again to add to your original order. Simply add the items to your cart and when you checkout, the order will be added as a new batch to the original order.

The order status will change to Updated, payment status to None, the order date, order status change date and order payment status change date will be set to the current date. Order will also be flagged as not invoiced and drive thru e-mail not sent.

Invoice and Payment:
After you submit an order, the seller should send you an invoice within three days via e-mail including your grand total and information on where to send payment. If you haven’t gotten an invoice within this time, you should contact the seller. If an invoice has been sent, the Order Total on your Orders Placed page will be in bold text.

You should send payment to the seller after you receive an invoice for your order. Please do not send payment before receiving the invoice since the grand total will need to be updated by the seller with shipping and other charges. In addition, the PayPal account address (if you are paying by this method) may be different from the email address from which you receive the invoice.

After you send the payment, you can optionally change the Payment Status on your Orders Placed page to Paid. When the seller receives your payment, he or she will send you your package.

After You Receive Your Shipment:
On your Orders Placed page, please change the Order Status to Completed after you receive your items, have verified the contents of the order and are satisfied with the order and consider the order to be completed.

You can also optionally Post Feedback to your seller after you receive your items.