I was surprised to stumble upon Signwell service. I have finally found the definitive answer to my question: How can I sign my electronic documents easily and fast with reasonable cost and reputable service? Signwell is so easy to use it is delightful. You upload your own file. Define fields for sign and other data (text, date ... etc). Send the file to recipients through e-mail to be signed in parallel or in sequence. And after the recipients sign through a friendly interface, the file is uploaded into your account. That's it. There is no need for external verfication and no third party software. You only need a browser. The file is recognized by major PDF software e.g. adobe and foxit as a valid signature. The service will integrate with other platforms like Trello, slack, gmail and others through Zapier. I have contacted customer service for a couple questions and they have been very helpful even when I was on free plan.

This is by far the best service for sending and receiving electronically signed documents. The interface is intuitive and easy to navigate.

I appreciate that it is free, we have 2-3 docs a year that need an e-signature and we are a small business where every dollar counts, it is a great service to us to not have to pay a monthly or annual charge for the small amount of work we need.