Retargeting tips?

Hello guys!
I had a little problem. I got a pdf and i got an audience. I want to giveaway this pdf( i want to upload it to amazon aws and give it to people) but let´s say that i will upload it to a landing page on clickfunnels.

Now, i have an upsell ( affiliate product) at the bottom of the pdf but the question is: How do i know which people bought the offer and which don´t? I need that because i want to retarget thpse who didn´t buy through another ad on facebook.

Well, it would be safe to say if a prospect ended up on your sales page that they clicked the upsell link. Install the retargeting pixel on the payment page of the sales page

blackbeans said:

Well, it would be safe to say if a prospect ended up on your sales page that they clicked the upsell link. Install the retargeting pixel on the payment page of the sales page

Click to expand...

Yeah but the problem is that the product it´s not mine, i´m promoting it as an affiliate and i don t know if i can install the pixel on the checkout page