Redo the rental website. You must know Netflix or eBay to self inspire on the design model. We already have the mechanism of the currently running e-commerce. So redesign and retrofit Google Checkout, bank account, credit cards and PayPal on the site. Put the same logo on many websites.
Provide a wrapper that can be printed out on regular printer paper, with mailing address and the sender's return address. Secure an option to print postage directly onto the wrapper.
Show us your previous work design examples. You must also sign NDA.