I can do that On/Off module for you. I've worked with a lot of OpenCart websites and built some really complex solutions, I can provide screenshots on request. I have also developed multiple OpenCart payment extensions (AsMoney, 2000charge, Blockchain API). If you don't agree to the price or the time needed, I'd love to hear your thoughts. Please contact me to discuss project details. I guarantee that the work will be done in the best quality and on time. As well, during the development of the project I will always be available via e-mail and Skype.