Photo Editing, remove simple background from photos & resize

Hi! I need approximately 80-90 flat shot product (jewellery) images edited - with white background, possible increase colour intensity, and resizing. Some images will only need editing once and then resized into 3 different sizes. The photographs have an existing white background but it is not crisp and there are shadows and they all need to be removed and replaced with a crisp white background. The products may need sight colour adjusting to make them vibrant enough for a website. They also will need to be resized - JPEGS 300px x 300px, 140px x 140px, 70px x 70px or 600px x 400px and then a high resolution PSD file of each. Square Images: The product needs to be in the middle (300px x 300px, 140px x 140px and 70px x 70px) Rectangle Images: The product can be either size (not in middle) (600px x 400px) I will let you know which image needs what size. I have attached an example of a product photo that need editing (the attached needs to be edited as above and resized at 300px x 300px, 140px x 140px and original high res size PSD file). Need this done as soon as possible. For any questions please do not hesitate to PM me. Thanks