Supliful operates on a margin-based model, which means there are no upfront costs to build your brand. On the Free plan, you can take as long as you need to design products, connect your store, and publish products, all without a paid membership.
However, when sales come in, you'll need to upgrade to a Pro Membership or an Enterprise Membership to fulfill orders. If you want to learn more about how Supliful will charge you for incoming orders, please take a look at this article.