create ad space to sell ads on our site a openrealty php job

we would like to sell ad space as per the excel info sheet attached so need our homepage modified or dovetail onto a freeware ad management system if it is easier each ad has to have a link to advertisers site so that when enquirers clcik on the advertisiers link it opens to their site (if they have one) in an embedded page so they dont go off our site we will want to change the contents of each ad position manually once a month and easily or you can as the contractor do it for a set price if you can do it 24 hour turnaround