Presuming you have a promotion or discount and you want to add it manually to your product in the SELL menu or change the price manually in the SELL menu, you can record those changes and see it in the following steps:
I. Discounted Sales
Step 1. Create Discounted Sales
Discounted sales happen when you create a new SELL invoice with a discount in it.

Step 2. Discounted Sales Report
After the payment completed, you can check the reports in the following menu:

Column | Description | Example |
ITEM % | Product Discounted Percent | 15 |
ORDER % | Invoice Discounted Percent | 15 |
ORDER2 % | Invoice Discounted Percent | 15 |
ORDER % AMOUNT | Invoice Discounted Amount | 15000 |
II. Price Change History
Step 1. Changing Price From Sell Menu
Price change happens when you change a product price from the Sell menu. In this scenario, we have a product named 'Captain America T-Shirt (Large)', the normal price was Rp. 200.000,- and we changed it to Rp. 150.000,-

Step 2, Price Change History Report
After the payment completed, you can check the reports in the following menu:

Note: click 'Discounted Product'

You can see the original and the edited price of the product.