Hello there

I am building a travel website that will be launched in early 2013. I hope that it will become a major player in providing customers with travel ideas and inspiration and thus compete alongside the likes of Trip Advisor, Lonely planet among others, at least that is the aspiration.

While we are some many miles from that achievement, in the interim I need to set advertising prices. But how can I do this when I cannot determine the amount of traffic coming to the website. Should I wait for traffic to grow first before offering up ad space, or settle on an intermediary pricing structure? If so, how best to determine that pricing structure?

Any thoughts?