Add Features to PHP invoice Script

I need to add features to this open source script , Bamboo Invoice - demo / download from here [login to view URL] ----------------------------- Add quote feature All same features as invoice e.g. Quote summary , Private Note , etc .. Option to convert quote to Invoice. Add Predefined Signatures - for sending quotes via email, at the moment when you select email invoice it has a text box to enter the email message, so it would have an option to use a predefined signature or enter custom message. Make the Client Fields editable - option to edit and add new fields. Add Search For customer - by quote , invoice - by name , reference or any fields under customer profile For new invoice - under select client - add in option to search by - name or client fields , or select from drop down which already exists. When creating a new client under clients or under add new invoice , add contact to the client at the same time . Add Feature - customer import , import customers from csv or excel Add A product feature , where we can add products and save them to be selected when capturing invoices/quotes. when adding a new product , option to select weather product requires lease or not. Only Applies to products which require a lease - Add leases - from template - customer fields will be automatically inserted if the customer accepts invoice. When an invoice gets emailed , add feature to send a link with the email for customer to accept the qyuote/invoice If its a quote and customer clicks "accept quote" in the email , automatically convert to invoice and send to customer. If invoice is a accepted via the link in the email - customer goes to a page where they complete all fields required for the lease . the lease is generated based on the product and template and customer info inserted , and it is then displayed to the customer - They must then Click - I agree to all the terms and conditions of the lease, this should add a digital signature with time/date stamp onto the lease and give the customer option to Save or print it. Add Leases Menu under leases - view list Leases must have status's e.g. accepted, pending , not accepted and be available for admin to view/download/print.