[Cpt.Crashtastic]

If we are talking about a customer being able to attach something like an image to an order then here goes.

My ideas

Admin should be able to define when and where the file attachment occurs.

For example if a customer is buying 3 sizes of shirt for a printed logo, he does not want to upload 3 times. PIA. Ideal solution would be uploading at or just before checkout

You could have a possibilty of the customer managing his own attachments and being able to select his prefered image on the product page that he has previously uploaded. Of course upload should be available from product description page also. Again PIA for the shirt example but ideal for a printed mug.

Any uploaded images should show a link or thumb in order details on invoice and in cart.

It should be possible to define which products have the possibility of uploads.