Hi there jkelly-rpmig-com,
Thanks for reaching out about emailing estimates. QuickBooks Online is a great tool able to help you create and send sales forms such as estimates and invoices so your customers know about the services you offer. I can provide some information about electronic signatures.
When an invoice or estimate is sent from QuickBooks Online, there isn't an option to include a signature. One possible way to accomplish this would be by connecting a third-party app. To see if there are any available that would suit the needs of your business, go to the Apps tab in QuickBooks Online, then search for relevant terms in the search bar. To see more information about an app shown in the search, click on it, and information provided by the third-party developer will be displayed, as well as some reviews from other users that have used the app.
If you have any other questions, feel free to reach out here.