Build a Chrome extension for Hubspot CRM

I need a chrome extension built for Hubspot CRM. It will interact on the frontend of the site and also via the Hubspot Developer API. Attached is a mockup of how I would like it to look (just a quick idea, open to a better designed solution) - it's inserting a box within the notes section that allows for quick disposition against a number of fields. When the note is saved by the user, the values in the new fields should be posted through the Hubspot Developer API to the corresponding fields in the contact properties. When a contact page is loaded, these values should then be retrieved from the contact properties via the API. Please give some details explaining how you will solve this problem in your proposal.