Suggestion for mutiple price option

Hello Aronium, I have a suggestion. Could you upgrade the section of the sale price to a multiple of pricing options. For example, these 3 price options we can list them into categories as low, lower and lowest prices / net price. There are customers wanting to buy something worth $ 50, then they are asking price reductions, so when we put the goods into the system, the multiple price options will appear, three prices are $ 40, $ 30 and $ 20, the last price $ 20 is the net price which can not be lowered, if the employee tries to enter the bottom value of $ 20, the warning box will appear to say the price can not be changed. Its like discount method but for me it's easy to explain to customers that prices are no longer altered and will be easy for employees to handle that customer. So I think, a lot of price options are easy and better. But, discount method also should be maintained in your system. I am very happy and enjoy use the Aronium POS system. I hope you can understand what I say and consider this. Thanks. 

I summarize the above suggestions:
1. upgrade the price section to 3 price options or multiple price
2. create a warning box that will appear if there is a lower price entry from net price