Can we setup a contract in Omni Price for a buy one, get one promotion?
Omni Price does not have a specific feature where you can setup a Buy one, get one promotion. If you are working with the same item, one suggestion would be to setup a contract and use the Start and End Quantity fields.
For example, Say you are running a Buy one, get one promotion on Phones. Each Phone is $10.00, but if the customer purchases 5 phones, the 6th one is free. You could setup a contract where Omni Price would use the price specified in Great Plains if the user purchases 1-5 phones (Pricing Mode = No Special Pricing). The second line on the contract for the phones would include a special price (Fixed price) if a transaction was entered for 6 phones (Price Mode = Fixed Price, Fixed Price would be $50.00 (5 *$10.00 plus one free phone).
If you are running a buy one, get one promotion where the user purchases 5 phones and gets a free headset then you could set up a Kit Item and create a contract to assign a special price to the Kit.