Hi,I Have read your project description.i have 8 year exp. in opencart.
I have excellent exp. In opencart customization, module creation/upgrade, theme customization, theme creation, any type of opencart work will do it. i will do it work perfectly as per your requirement.
i will uninstall the multimerch extension on your website.
Please come on chat to speak about your requirement in details so we can start project as soon as possible.
Looking forward to hear from you. Thanks.
Regards
Sandeep P.