Custom WHMCS add-on required

Hello, I need a custom add-on that allows me getting time response average for employees in WHMCS Features & requirements for me: - knowing the fastest employee in responding. - getting a list of employees with their average time response ( everyone with his rank ). 1. You will check the response time between the support operator and the customer. If there will be 2 answers in a row ( for example operator-operator or customer-customer) , then you will not take this response time into consideration. In other words, you will search for answers considering a pair of answers. 2. the ticket response time will be only counted on tickets that are with "Customer-Reply" and "Open" status with last response from the client. Note1: I need this add-on to be lite on our database and don't over load our server. Note2: My WHMCS version : 6.2 Note3: I'm searching for the best quality with the best and suitable price too :) Thanks.