add discount feature to individual products on website

We have a custom website with over 1000 products. Currently we run sales and discount products with discount codes that can be applied during the shopping cart checkout. I would like the ability to add discounts i.e. 25% off to certain products so customers would not need a code for some sale items. This feature would have to be configured so I could select multiple products at once and publish them all together. It would also have to be configured so I could manually choose the % to be applied to various products. The selected products that will have the percentage off also would not be allowed to use the coupon code feature during checkout so our customers could not do double discounts. I would also like the listings show original price and the markdown price. To view our website [login to view URL]