Sales Commission

Hi Excel Gurus

I have a semi-difficult one. I cant get my head around it...

so, I have a commission calculator. We sell 3 items (Licences, MOdules, Services)
Each item has 3 bands of commission %. For example

For Licence sales of <125K, I earn 4%
For Licence sales of between 125K & 250K, I earn 6 %
For Licence sales of > 250K, I earn 10%

The same goes for MOdules & Services.

I have an excel table with the following information:

Customer, Description, Order date, Type (Licence, Module or Service), Sale Value, Commission Rate

What I'm hoping to do, is find a way that I can have my commission calculated automatically using the % breakdown above.

so, I've now confused you, but pls let me know if you have any questions...