Image Editing work in Photoshop

I have launched an e-commerce website for selling Apparel. The project would entail altering the images / photos that we will take and send of the products by doing the following : - cropping and resizing them to a standard size - whitening the background so that product alone stands out To begin with, we have about 5000 to 6000 photos which must be altered. Thereafter, we would also want to use your services every week on a regular contract basis so that our new products which will be introduced every month can also be similarly altered. I want someone to start off on the initial set of photos on a fixed price. The new photos altering work can be discussed separately following this. We want the work to be completed within 30 to 35 days.