Adding Images to multiple items - ongoing work

I am looking to a Adobe expert who can quickly add designs I send to them to multiple selections of clothing. For example: I will send an image that I want to put on a T-shirt. I need it then added exactly the same to say 20 different colours of T-shirt. I then need the jpegs sent back to me. We will be introducing new designs all the time so I preferably need a set price to add a simple image to multiple products.