#1 - Check out the industry standards and research what you can and should offer.

#2 - Work on price breaks at approximate sales numbers. Eg, a software provider for SME's, might have price breaks at 5 users and 10 users whereas a program sold to multinationals will have price breaks at 250 users etc.

#3 - Work out the maximum discount you will give and make that for the largest volume and then work your way backwards from there.

All the Best,
Brad Sugars