It is sometimes hard to extimate the costs of advertising and your team might be reluctant to get into it incase it costs more than they would like to spend
You might like to point them to googles ad words and yahoos bing ad in total £80 of free ads - In that way they can test out free of charges and find that they can advertise for just $1 per day.
Dont forget to tell them about the key codes so they can see how many people click through from the web site/s
