Rotation of Offers

Forgive the basic nature of this question, but what is the best way to display CPA offers when you have an audience that is repeatedly coming to your page. In my case, I regularly draw users from Facebook and other sites to my page- but usually its the same set of people (a total pool of about 17K- with a few hundred coming each day). My problem is that if someone comes to the page, but has already completed that offer (ie: a free survey), then if they come back another day and the same offer is displayed, I lose out since they can't/won't want to do it again. Is there a way of setting up a rotation such that in the event the user has completed an action on an offer, a different offer is showed to them.

Separately, would you recommend I just regularly rotate different offers daily? The problem I had with this is if one offer is working really well, I would have to sub it out completely simply because on one day a few hundred used it.

Thanks!!

C'mon people; someone's gotta know this...

I would set a cookie to the visitor with the number of the offer, he visited.t
When he user comes the next time, the rotator should read the cookie and send him to the offer which wasn't visited yet.

usually you can setup call backs with the cpa system

somehow identify the user with a cookie and insert the id into the cpa offer and when you receive the callback you need to store the id of the user and the id of the cpa offer the user completed

now when the user comes back, you check for the user id and use the id to check for completed offers. if there are you just filter the completed offers

i know maxbounty and ************** have callbacks, other cpa programs should have it too