It depends on the company you are dealing with. I own a quilt shop and was a rep for HandiQuilter until health problems made it hard for me to install and service the machines. They are very heavy and it was very hard for me to lift them.
I made the sale for the company and the machine was then shipped to me or direct to the customer. The customer had the option to set it up themselves or have me come to their place and set it up. I then gave the customer instructions on how to use the machine and when I filled out the information from the lesson and mailed it to the company then I received my compensation. It was a set amount so any rep (dealer, shop owner) got the same amount no matter how much they did.
As I said it depends on how the company is set up and how they word their contracts with the people that sell their products.