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1- need help with adding some metada for the products. like expiration date, weight, which i am clueless with woocommerce functions. 2- also for my account for them to see "Savings", "Bag" and "Weight" scores. for example if we know the full price is X, and discount is Y, we know savings = X-Y. I think we will add new attribute 'Saving' for every product. When you create/edit any product, you fill Normall Price, Grub Price... and click Save. We will trigger a hook to calculate Saving value (X-Y). then it depends which price they want to pay. if they pay full price, then there is no savings, but the savings is interpreted as Grub Bag. what this business does is sell items at cheap but if customer wants to buy at full price, the extra they paid is used to buy groceries (Bags) for the [login to view URL] will tally with their cash intake so they know every week or month how much money they have for grub bags If they pay discounted price, then there is no money to buy grub bags but we wanna show them that they saved X-Y amount of money. for weight, regardless they pay full or discount, weight keeps accumulating. lets say u have bought 4 items, and all weigh 0.5kg, then you weight of food saved is 0.5kg. we later want to use this data for two things. a leader board (who has saved the most money, weight or bought grub bags) and also display total of ALL savings, weight and grub bags funded for all users. the current site has this display but i update the numbers when we can. 3- we would like to give them an option to buy at 2 different prices. each product has 2 prices. one is a discounted one and one is an original price. example. tomato ketchup at RM 20 (normal price), and RM 10 (discounted price). We would like to put beside the higher price that RM 10 (the price difference) will be contributed to our Bag if they buy at RM 10, we tell them they saved RM 10 at the shopping cart page and also when they buy, we add in their "Savings" score +RM10. If they buy at RM 20, we tell them they donated RM 10 to our Grub Bag (groceries for the poor) at the shopping cart page and we add in their "Grub Bag" score +RM10 4- all of the above is when user buys something from a particular product category (the above tomato ketchup is from category grublist). because they are other categories that may or may not fall in this group. if an add on plugin would be great so we can keep the core woocommerce files untouched.