Woocommerce - customize Cart and Checkout - prices to points for certain product category -- 2

I am looking for a Woocommerce developer to help me tweak the Cart and Checkout to the needs of the client. Each customer while making purchases earns points after the checkout and those points are stored in his account. Later on the customer can buy certain products (a separate from the regular ones) for those earned points, where each point = 0.05 currrency (dollar), making it 200 points being worth 10 dollars. We've started to program a function plugin to take care of the backend part of managing the customer`s points and also been able to convert prices of a certain category of products to their equivalent in points. We didn't touch neither the Cart nor the Checkout, though. We would like you to update and add more functions to the exising plugin. Here is what we need in Cart/Checkout: 1. Point-products can be added to the cart ONLY if logged in user have enough of points earned 2. Prices of point-products need to be converted to points in Cart and Checkout 3. If there are any earned points, they are shown in the Checkout (cart) so the customer knows how many of them s/he have left 4. There could be mixed products in Cart/Checkout a. regular priced products are treated as normal b. point-products deduct the number of points from the customer quota on the fly and are NOT counted into total price 5. The total price should be displayed ONLY for regular priced products 6. Shipping can also be converted into points (if there are enugh left) Also: At this moment all point-products live in a separate category and only THIS category which isn't the best solution. We would like the category (it is called "program-partnerski") to be added to any product so it could live in many categories. And now: 1. if customer adds a product to cart and this product is also available to buy using points an info should be displayed "you can buy this product using points" and then "convert to points". This ONLY if there are enough points in custmer`s quota. I will provide the answers if you have any. The point system operates using WP tables (post, postmeta, user, usermeta) + 2 separate tables storing points, which SQL to I will provide. I will upload the current plugin to Bitbucket, so you'll see what have been done so far. What would be the cost of such tweaks to the Cart and Checkout? What would be the delivery time? I look forward to hearing from you!