Build a jQuery email template builder - Html/Css, jQuery

We are looking for a new email editor website to allow our customers to build emails templates online. We would like the application to look and function similar to the template creation of these applications - mailjet, mailchimp, mailgun etc. On top part of webpage there should be top bar with elements (text, title, subtitle, image, etc.). One of the elements should be a table layout allowing for different number of columns to be added and allow user to drag and drop into email area, and drag and drop other elements into its columns. User should be able to select from several premade templates or design their own. You can use any free JavaScript scripts, or templates or whatever you are able to make the development faster for you. Please send me some sample applications you have worked on to prove me your expertise. If you are interested in this job, please show us some wire frame mock-up of how you envision the application working. After we choose the candidate, we will talk more about features so you won't be doing any unnecessary development. Please show us some of your sample work as well and explain to us why you will be the perfect candidate to do the job.