Customize WooCommerce functionality and plugins

We need a few things custom coded for our Wordpress/Woocommerce site. Currently, we are using Subscriptio plugin for users to rent items from us. 1. We need to be able to rent out our products for X months as $X per month (we should be able to set this number in backend or hardcoded into the plugin). For example: We want the customer to pay $50 a month per 3 products they checkout with (if they select 12 months). If they checkout 1-3 products, it's $50/month. 4 - 6 products = $100/month. 7 - 9 products = $150/month, and so on. If they checkout with 3 products but for 6 months, we want to charge more (maybe $75 a month). We need to be able to set: $X/month for X months. 2. If user cancels before the last month, they will be notified that they will have to pay a Cancellation Fee based on the agreement when they first rented the product. 3. We need to hide all product pricing on site (throughout category, product, cart, checkout pages). 4. We have a submission form. This form was created with gravity forms. We also have a delivery date/time plugin for user during checkout. We'd like to also inject this plugin functionality into the gravity form so when user submits form info, they can select a date/time which would be registered into the same plugin. 5. We have a plugin called Dokan (seller marketplace). It currently only allows a User Role to be seller if user includes fields like: "First Name" "Last Name" "Store Name" "Store URL" "Address" "Phone" I'd like to remove these requirements so a user can become a user by only including email. If I set user to be seller in WP backend, they will still not have functionality in Dokan Dashboard because it requires those fields. 6. Currently, Dokan plugin pays sellers if products get purchased. We would like to credit sellers ever month the product is rented (not just 1 time credit) based on the product price in woocommerce backend.