This article completely missed the technique which worked for me - adding a notation to every invoice. I would put (2/10 1/20) which means to accounts payable t

This article completely missed the technique which worked for me - adding a notation to every invoice. I would put (2/10 1/20) which means to accounts payable that I will give a 2% discount if they pay within 10 days, and a 1% discount if they pay within 20 days. After doing that, I consistently got paid quickly (at a discount - so your offerings must be priced to give those discounts.) Every accounts payable department looks for such discounts as a routine part of their job.