What Payment gateways does Weebly offer?
Weebly offers Stripe as the the payement gateway on the Free, Starter and Pro plan. While on the Business plan you can choose from Stripe, Square, Authorize.net and Paypal.
Can I increase the number of products I can sell on my Plan?
If you want to increase the number of products you want to manage/sell on your Website, you will need to upgrade your plan.