Buying LED display, how to save 100000USD a year?

There are more than 500 LED display manufacturers in China. When you write emails to all these LED display suppliers,

99% of them do not know how to save 20% a year.

Why? Most of them have no idea to save the total cost.

If you cut 20% discount,most of them will change the material.

If not changing the material,how to save 10% a year? 

If not changing the material,how to save 20% a year?

In the same material,how to save 30% a year?

All of them are business skill.

Would you like to know all these business skill?