I dont know if this is the place to ask this but i figure it the most relavent

ok one guy told me that he makes money off companies putting their ads on his website. he sais that he cleared off a little space on his website and companies pay him to but their banner or link on his site. not like pay per click but like for him to put the banner on his website for a day or 5 hours and so on. He sais he gets payed 500-700 for each banner. I want to do the same but i dont know how much to charge. is there like a rubric to it. for example like if you have 50 people coming to your site then its 100 dollars for and hour. Can anyone tell me more about this system?