Completion work on a classifides ad site needed

Required to help complete and modify a classifieds ad site that is pretty much 80% of the way done. Was working with a site designer and then poof one day I never heard another word from them for over two weeks and have not heard from them since. The classifieds ad site will be developed and changed over the years to come and hope to evolve and change it as the years go by. Payment will be in the form of $50.00 dollars Canadian and then there will be another amount of money I am willing to give once the site starts generating money that will be discussed privately between I and the person I choose to trust with this project. As well as the above two mentioned forms of payment I will also give you a paid ad space on the site for the next 3 years once completed. With in a year I hope to be to the point of advertising on radio and television. What I need to know from you is what skills can you bring to the table and what can you offer in the way of helping to market the site once completed.