Has anyone had any recent or past experience on how much commission a broker should receive on a approximately $1,000,000 sale?
Sale of what?
For real estate, here it runs from 4-6% . Everything is negotiable. They may be willing to negotiate a tiered system. Lower if there is no split with a cooperating broker.
The best time to negotiate commission is at the time you are considering an offer if it is less than your asking price. There is nothing wrong with asking the broker(s) to help soften the blow to you in order to make a deal.