Hi, I am having trouble finishing setting up my store, thank you for your help.

Situation number 1: when a person is completing the payment process, they have the option to invoice their purchase or not request invoice, I want to disable this option, since the recommendation of my accountant is to invoice all global sales per month and not invoice each purchase or give that option to the customer, I only require the customer to enter their products to the cart and that the sales process is without the option to generate invoice, I only require their address for shipping their products.

Situation 2: I have different shipping methods or the option to deliver the product in a pick up place, but when a customer makes the purchase process, it automatically gives the option of home delivery, what I want to do is to add a step for the customer to choose if they want standard, express or pick up and then put the shipping address if applicable.

How can I make these changes? 

Let me know if I have explained myself well or need me to be clearer please. 

Thanks