Create invoicing app for wpmu network

Hello, I need someone who can create plugin for invoicing clients. Basicaly from wpmu admin panel I must to be able to mark invoices as paid, track incomes, and set monthly price to each plugin. All who use multisite in their site wpadmin must to see all their invoices (and marked as paid or waiting for payment) also It must to send them email with link to invoice(they need to be logged in before checking it) and in invoice it must to be possible to get invoice in pdf.