express 1 page checkout

We have a webshop build with Xtcommerce (simular with OScommerce, only php is separated from html). XTc uses almost the same structure of OSc 2.2. If you are interested in building an express checkout page for our shop, then please let me know and also inform me about the fix price for the job. I suppose that you develop this page with PHP + jQuery + Ajax. The project is already setup and coded but there are some issues not done which are very important when running this module. Code what is missing or incomplete: 1.a Change [login to view URL] so that [login to view URL] will be the new checkout including the class checkout_simon.php. Otherwise it will be difficult to test the login and register procedure. 1.b When customer likes to checkout from [login to view URL] he should get the option login as registered user and via a popup screen in [login to view URL] type his login data (email address + password) 2. I cannot switch to an other saved address 3a. If chosen a shipping method the total block not refresh correct and the shipping prices are 0.00 or not complete. 3b. If chosen Saturday there is not shown any payment option (only ideal). 4. Coupon code: 03ac275e_org (discount) . Should be added to the order. In admin there is in the lef column an Item Waardebonnen, click on it and choose -Tegoedbon Email. Here you can send you all amounts of coupons. An other general coupon code is: 03ac275e_org. that is active till8 july 2013. Choose in admin Waardebonnen and then the option Waardebon Admin. Choose an item and change the date to activate a coupon so you can test that one to. 5. How did you hear about us; should be saved into the order. 6. Gift wrap 5.00; Amount should be saved into the order as an extra product row. Bid on this project only if you have excellent proven skills (OScommerce is very important). You can get an impression of our shop at test.ts24.nl. I have an image as an attachment so you can see what is done.