Given the large community of ERPNext users, I believe that if you allow for Hub to become a platform for price reference from users, it will be one of the most highly sought after features of ERPNext.

The expected behavior is to have the user with products for sale, list them on Hub. Whenever the user updates the price (either on the Item itself, or depending on a Sale), an weighted average per unit is calculated, to be listed as a "reference price" in one of the Hub pages wtihin ERPNext. Thus, if I sell 2 carrots on same day to customer A, and one carrot to Customer B, the reference price for the day is a weighted average of ( (2 * Rate for customer A) + (1 * Rate for Customer B) ) / 2 = Weighted average price for day X.

This price would be tracked "As invoiced" and "As quoted", because there might be variations in what a quote proposes, and what the final invoice reflects.
Hub should then show:

• Weighted Average Price per day

• Historical view of price behavior

• Price "As Invoiced" or Sale price

• Price as "As offered" or Quoted price

• Datetime field of individual price entries (if desired to be viewed by user) and a single view with average price per day.