Copy new subscription tool to another of my client

I want to install the same news tool we did for one of my clients. We used Php and mysql I already installed the DB and uploaded to admin folder for my new client. I just need some fine tweaking on the front-end and the DB configuration. Let me know if you can do this quickly and what will be your cost for installation. I want to try to sell this turnkey news tool to my other clients, so there may be more to do.