Adding Additional A La Carte Digitals To Collection?

I have it set up that when clients purchase a package, they can add on additional digital files for a lower rate than if they were to purchase them a la carte. Is there a way to make this available to them ONLY after they've put a Collection in their cart? I had someone just order the cheaper one today only and I'd like to try and avoid that in the future even though it says on there (Added to Collection ONLY)

Edited by

See this article on how to do that:
https://www.picturespro.com/sytist-manual/articles/offer-additional-products-in-collections/

Edited by

Ok, I got these set up, but it isn't displaying the price for the additional image, just a little shopping cart icon. I'm also trying to attach a JPG and PNG screen shot but it's saying I don't have the correct file type :-/

Edited by

If it is just a shopping cart icon with no price, then I suspect you don't have a price for the extra photo AND extra new photo. You will need to set a price for both.

Edited by