Update and finish E commerce website

I am looking for a top class programmer to add functionality to my e-commerce website. The website will be a designer's showcase to sell fabric designs, and also an e-commerce shop site for visitors to buy those designs .

The e-commerce (shop) part of the site is already built, but my developer was unable to continue the project to add the following functionalities due to staffing issues.

1. Create a custom image upload facility to allow users to upload fabric design "source" images to the website in various common image formats; to have those images converted to jpg "on the fly" and to have them shown instantly in a preview box on the web page; for users to be able to choose a layout and print size and to have the image preview scaled and repeated in the chosen layout and size (eg. mirror, half-drop, half-brick etc) to show as a representation of the finally printed fabric. Customers selecting an image from the shop pages will have the image shop selection sent to this layout page with the layout already determined - they just choose the size of print required. Therefore images in the shop must have a way to be tagged with the layout the designer wants for that design, which carries through to checkout. The image preview is to include measurements of the final print shown on the webpage either as text next to the image or as small simple rulers scaled to the correct size (determined by the dpi of the image and the chosen size of the print).

2. The preview image on the webpage must be dynamically changable according to user layout and size selections (eg. mirror, half-drop, half-brick etc) and refreshed in real-time.

3. Create and integrate into the site a designers' or users' private/secure portfolio/account control page where the designer can create a biography; view and tag their uploaded images with description and seach tags; to indicate to the site owner that individual images be listed in the "shop" pages for public sale; to chose images to be printed; to select their own design for printing for themselves; see their purchase history and re-order past purchases if wanted; view current order statuses; view commission balances. This would need to integrate with or utilitise the existing shop site. Shop payment system will initially be Paypal (it's already built into the e-commerce shop).

4. Images uploaded would need to be pre-vetted by the site owner prior to listing on the site. Only the jpg preview images need to be shown on the site, the full-sized/full quality images need to be stored securely on the server for later download via secure FTP by the site owner.

5. Designers can earn a commission on sales of their designs and the website must be able to handle the commission calculations so as to update commission balances. Commission balances need to be available to the site-owner so that commission payments can be made to the deisgners (monthly).

NB: The printing operation is not a part of this job specification.

There are some more details which will be made available on request. I'm looking to have the job completed within 4 weeks of starting. The website coding will be made available to work with. The site must be made available on a test server for preview and full testing will carried out online prior to job sign-off.

I would like to receive the work weekly.

Thank you very much