How do I set up a default warehouse and sales channel for a customer in Odoo 11?

1. At the moment, I have only been able to set a default warehouse for a user. But some users invoice from different warehouses, and so their warehouse is not always correct and mistakes are made. Is there a way to set default warehouse for customer?

2. I would also like to set customers into sales channels. It seems you have to set a salesperson to do it at the moment? But some salespeople work on different categories of customers. We want to categorise customers, so for instance Category A would have Price List A, Category B would have Price List B and Warehouse B. We want to see how many sales by category of client.