Hello,
we have got very long and sound experience on WHMCS, Smarty templates, different API's, and MVC framework and would love to offer our services for building of WHCS plugins.
we have all the needed experience but can not show you the live work due to client's agreement restrictions but we are top ranking team on Freelancer with 500+ completed projects and request you to see our Freelancer profile for past track record.
we are even happy to build first module on fixed price and if you like the work and communication you can hire us on hourly.
Best Regards,
Lx