The best way to complete a multi-item order is to add each item to your Cart and then checkout with a single payment; all discounts will apply automatically. If for some reason the shipping cost does not look correct, click "Request Total" or send me a message BEFORE confirming your payment (don't worry, once you've requested a total, items in your Cart cannot be purchased by another buyer.)
To keep costs reasonable, orders up to 20 cards and/or $25 will generally ship as reinforced flats; larger orders are generally shipped at package rate with tracking. (Package rate postage with tracking on smaller purchases is available on request for an additional $2.)