Sorry, paypal only. When I list cards, I do it by the dozens, and when they all end I like to ship them out in batches so none fall through the cracks. Waiting for cash to arrive (risking it getting lost) or worse yet, having to wait for a MO then find time to take it to the post office to cash it, takes way too much time and complicates my life to the point where it's not worth listing cards. Just trying to keep it simple and make sure everyone gets their cards quickly. I do combine auctions though, so if you buy more than one item, I'll ship for the greater of (highest auction shipping price) or (actual shipping cost of all items in one package).
I'm happy to combine shipping on multiple items. Total shipping cost will be the greater of (1.) the highest shipping cost of any single item, or (2.) actual shipping cost for the lot.