Upgrades to bitrix

Good afternoon.
Interested in the improvements in the bitrix. It's part of the job. I will send you a full list after the conversation. Interested in the cost of work and timing of implementation.

1. Order handling:
A. freezes when canceling an order, changing status, using the "delivery" button.
B. It does not allow you to delete the order, it gives a fatal error.
C. When forming orders in the adminka, automatically pulls up a discount of 2-3%, which should not be.
D. when adding additional goods to the order with a discount, the discount on the newly added goods does not apply. The link “recalculate the discount” does not work.
E. When you create an order in 1 click, you will get a fatal error. The order in the adminka is displayed, but there is no name, no phone, no commodity items in the order itself.
2. unloading in bitrix-1c-retail-bitrix. Requires a check of operability, configuration of the connection (readiness of unloading at the moment - 90%)
3. Formation of product links when automatically loading goods from 1c, dynamic links when using filters. Currently, links are not generated either for the product or when using filters.