digital signatures included in price?

Do we need to purchase a separate product form a digital signature service such as docusign to use your service to gather digitally-signed documents?

You can actually use our Signature field so you do not need to pay another subscription from a third party service.

How-to-Add-an-E-Signature-to-Your-Form

However, if you wish to use DocuSign, you would indeed need to subscribe to them.