Additional development to a current ASP system

We have had developed a calendar/booking job database using ASP language - the system is now live which our client is using. We need a couple of simple extra developments carried out on this program including: Approval system to be added - Once an engineer has logged a job an automated email is sent from client (e.g. ) to the user email address where they will be supplied with a link to for them to 'approve/confirm' that the work has been carried out by the engineer. We have some wireframe visuals to give you and idea on the alterations to system.