oscommerce store fixes

Oscommerce discount module fixes. I have a huge oscommerce store which has an add-on (not sure if contribution) but later was customized to accept custom coupon codes. I need to fix it as it seems that it has conflict when combining with other discounts. Need the following fixes/modifications. In OSC admin there’s a module called “discount” there I can create different discounts with an specific name, ending date, percentage of discount etc. Have been made a lot of changes and I would explain how each one works if necessary what I need is the following. • There’s an option for free shipping over 50, and discounted shipping for International customers, HERE I need that it’s only given after discounts and not “before” discounts. For example if order is 51 they will get the shipping advantage but it seems that after discounts are applied system is calculating the order total before discount, and giving the free shipping even if the final total was 20. • I had a weekend sale with a coupon for 30% store wide, but will need to have it reviewed because order were all messed up while applying other different discounts. The coupon code must apply to the already discounted product. For example if a product cost “10” and is already in specials with a 20% discount then it will cost “8” and if applying coupon then it should cost 30% over 8 and not over 10. (5,60) • For specials there’s at description page where the price shows something like : Price-5,95, Sale-5,32, You save 9,92%. HERE I need that at check-out there’s an extra line telling how much they have save. Under total. For example Subtotal. 10 , you save 2 total 8. • And last I need that when adding Item to cart they get the info immediately, NOW it all show at check-out “confirmation” even after choosing payment method which make them doubt if discounts are really applied. I need users to after adding each item to cart they get all info; shipping costs, savings if any etc. (I can show a website example with this feature). Please bid only if you are familiar with this specifications and if you are an OS Commerce expert! It should be ready before 5th September