Here’s an overview of e-signature solutions as of March 2019:
Scrive: Works perfectly and it’s free up to three documents per month. Perfect for many smaller businesses who sign very few documents.
SignNow: Cheap at $5 per month when paid annually. Drawback you have to place signature fields yourself.
Kivra: Great for Swedish businesses as it’s got mobile bankid support. This makes your agreements with Swedish parties extremely safe.
Adobe Sign: It’s not very user-friendly any longer. Back when it was Echosign I found it easier to user. Adobe don’t offer any email support and it’s difficult to get in touch with them.