On Curtsy, you decide who pays for shipping. 

When listing an item you choose whether to cover the cost of shipping and have it deducted from your earnings or have shoppers pay extra for shipping at checkout. We recommend making shipping free for buyers to help your items sell faster, but this is optional.

After your item sells, we'll email you a prepaid label to ship your item. If you don't have a printer, we can mail you your label. From there, you'll package up your item in any small box or envelope- we recommend reusing something like an old Amazon box. You can give your package to USPS or schedule a free USPS pick up. You'll mark your item as shipped in the app and get paid as soon as tracking updates. From there you can cash out to a debit card or bank account.