I feel like selling commodities is being handled in such a backwards manner. Why don't they just show the price of 1 tonne worth? Then when you sell it show a breakdown of how much you're selling, what the total asking price would be, subtract the scaling bulk discount, and then a final profit? Especially if we're talking realism, any vendor or buyer is fully aware of exactly what kind of discount is being given for a bulk sale, it's not hidden information (like is currently going on). This could also be used for bulk discount use on other trading, so for an example of let's say, Void Opals if they had a sell price of 1,000,000 per tonne.
Void Opals
- 100/100 +
Demand Price: 100,000,000
Bulk Discount: 5,000,000 (5%)
Profit from sale: 95,000,000
Purchased at: 0
Total Net Profit: 95,000,000
This way, once you've sold, at discount, your cargo at the stations demand rate, the station can update the price based on the new level of Demand and it's now lower price. If the demand is less than your cargo, it has to be 2 transactions; First is to the demand cap, sell. Then afterwards is at the cost of 0 demand, which one would assume never gets lower.