Zen Cart Customization & Addition of Wholesaler login

I'm currently using Zen Cart v1.3.7. I would like to change the payment method. Now we are getting the credit card information emailed to us when someone checks out. I would like to use a payment gateway such as [login to view URL] or paypal. This type of payment would only be used for Retail orders. Also, I would like to add a wholesale login section with approval. Here is the concept: What we would need to do is create a wholesale login section where wholesale customers can apply by uploading (or mail/fax) their resale number certificate (an image or pdf file). Then, once you get that info you would manually approve them to be wholesale customers. Once approved, an email is generated to them and they they can see the wholesale pricing after logging in. Then they would be able to view pricing and see our minimum order quantity per item for wholesale too. You can also give access to downloadable PDF catalogs, etc? to wholesale customers. The approval process should be easy and should probably integrate with the dashboard (once you login to admin you will see the pending approvals). A couple notes: 1. When the admin is approving or denying the wholesalers application, their should be a drop down menu with the choices for payment terms: -net 30/45/60, prepaid, COD (plus an option to enter in new payment terms). Wholesale orders will not be processed using [login to view URL], rather Zen cart will just generate an order confirmation via email to the admin and wholesaler and also store it in admin. Then the process will go manual and offline for payment as we usually ship out wholesale orders after 20-30 days and will bill them manually. If you can include a field which will state that they will not be billed now, but if they would like to enter credit card info now, we can save it and bill them offline. Maybe it would be good to use the current retail method of emailing the credit card info for wholesale orders? See details for more info: ## Deliverables Also need to have a shipping method option when people are filling in their wholesale orders. Our default method is Fedex Ground shipments. But some wholesale customers like to enter in their own shipper and type of shipment along with account number so then we would not bill them for shipping, but rather bill their account for shipment. We have about 100 products in our online store. I have a PDF document with the wholesale pricing and minimum order quantities in that. I will need you to do the data entry required in converting the PDF catalog into a format suitable for import into the database. Lastly, we need to move the admin for security purposes from /admin to something else. I will give you the exact path once you are selected. Hosting is on mediatemple. Database is MySQL. Kindly estimate how long it will take you to complete. Look at the attached document for screenshots from a similar site we had developed some time ago. Also, please let me know how you plan to launch this entire upgrade on the site and test it since its a live site.