Online order system

I'd like to find someone who can set up a simple online ordering system for me. I have my domain name and hosting through godaddy. I'd be happy with a framework like Wordpress and any of the open source shopping cart packages, but I realize that some customization would be required. Here's the issue: People will be ordering food/groceries online that will be delivered to them in person. If someone wants to order 5 lbs of apples at $1 per pound, that's fine. I want to be able to accept the order and then fill it. When I have their bag of apples and I weigh it, I see that it's 5.32 pounds. I want to have some way to edit the quantity to reflect the EXACT weight and then confirm the order and/or email them an invoice. From the email they should be able to click on a "Pay with PayPal" button or link and make a payment of $5.32, or they can just pay in person. I believe that there's an open-source solution out there, but I just don't have the time to sort through the options and put it together. I would prefer something that's user-friendly, since I'll have a couple of employees using it to accept and process the orders. I set up a test run on our main web page using Wordpress and the WP-eCommerce plugin and really liked how easy it is to add new pages, edit the themes, etc. After trying out four different shopping cart packages I discovered that none of them allowed fractional quantities (zencart does, but that's not one that I tested) and none of them had a way to accept checkout AFTER the quantities had been updated to reflect the actual amount being shipped. Right now I just have a fill-in order form which works fine for now, but I'd like something a little better. I've decided to use a separate domain name/hosting package to do the online ordering. This is perfect because I can leave my existing order form alone while I get the new one ready. Here's a few more details: It doesn't have to be Wordpress, but I want employees to be able to easily add information, pictures, edit information, and manage the web site. A shopping basket in a sidebar is preferred. I don't want people to be taken to a shopping cart page after adding an item. I want them to be able to just keep adding items to the cart while looking at all the products on a page or within a category. I want a text-only shopping cart. Some things might have pictures in the catalog, but not many. People don't need to see a picture of a piece of meat to know what it is. The look that I'm interested in is simple and clean. Not fancy. No animation, no fancy fonts. Security isn't an issue. We are a farm and all of our products are being delivered to someone's home or to a drop-off location. There is no checking out and paying...it's only requesting an order online. I encourage people to pay in cash or with a check IN PERSON. I'm not asking for you to do everything; you could just to recommend what I should use. If your recommendation is (just an example) Wordpress with XYZ shopping cart, I can install that and enter in ten sample products in the inventory. Then you can do your modifications/customization to the shopping cart back-end and we're done. Whatever is easiest for you.