Using two of the following: Kants theory, utilitarian, virtue ethics

You are preparing a competitive bid to submit to a customer (Big Box Bonanza) who has requested confidential bids for a potentially lucrative and long-term printing contract. Your main competition is Bugle Boy Printers. Your main competition is always Bugle Boy Printers it seems, who somehow manage to just undercut your price on a regular basis. They're decent printers, but they occasionally cut corners to beef up their profit margins, after having secured the contract by bidding low.

On a visit to Big Box Bonanza to review the contract specifications and details, you are given a sealed envelope with another copy of all the contract specifications inside. All the other bidders have already had access to the same information. When you return to your office and open the envelope, you discover that a copy of Bugle Boy Printers' bid has been included. Obviously, having a copy of your main competition's bid would be a tremendous advantage to you. You not only know their bottom line pricing, but also how they have approached the mechanical specifications for the job. You immediately think of several ways you could make your own company's bid much more attractive to Big Box Bonanza and land the deal. As a commissioned sales rep, that would mean a lot of money in your pocket - potentially a long term contract that would pay you an additional $50,000 a year, for many years to come. You don't know how Bugle Boy's bid came to be in the envelope you were given, but are certain it was a mistake.

What ethical issues are presented here? How would the two ethical theories you've selected deal with those issues? What would you do, and why?