Add new pages & logic to a WHMCS module

I'm building a small application to do basic bookkeeping in WHMCS. I have created a basic addon with an interface (see screenshot) based on a responsive template. What I want you to do is create the needed forms, logic, views, etc to do the following stuff: Manage suppliers: - view/add/edit/delete/.. - Each supplier should have standard details (Name, address, ...) and a standard booking account (just a number) & VAT deduction rate (0-100%) Manage purchase invoices: - view/add/edit/delete/.. - View all purchase invoices between certain period (with totals) - add the PDF invoice with the record (upload) - select the supplier for each record - add the amount (in/ex/vat) for each record - select the VAT rate for each record - select booking account for each record Manage booking accounts: - view/add/edit/delete/.. You also need to add the logic to create the database tables. All forms and views should be responsive (but the template already is) and input validation. You should only accept if you have some knowledge of WHMCS! All coding should be done according best practices & should contain comments. WARNING: PLEASE, ONLY BID IF YOU UNDERSTAND THE PROJECT SCOPE FOR 100%. PLEASE BID YOUR ALL-IN PRICE. If you place your bid, you agree that you can do the work as described here for that price. If you place a bid, and via chat you quote a higher price, your bid is false and will be reported to [url removed, login to view] (see Freelancer User Agreement). We release the milestone payment once we have the product working on our own server. DO NOT BID IF: - YOU ARE NOT 100% SURE YOU CAN HANDLE THIS - YOU CAN NOT FINISH IN TIME. - YOU DID NOT UNDERSTAND THE PROJECT FOR 100% - YOUR BID IS HIGHER THAN THE STATED BUDGET. - YOU ARE GOIING TO ASK A HIGHER PRICE VIA CHAT. - YOU WANT THE MILESTONE (OR PREPAYMENT) TO BE RELEASED BEFORE END OF PROJECT. - YOU NEED ANY MORE INFO (send me a chat or use public board to clarify anything).