So when you see a portable TV on sale for £100 you know it includes tax of £14.89.
Now let's say I have that TV in my shop and I'm offering a coupon of £10. What I want to do is give a customer £10 INCLUDING tax off the TV, not £10 plus tax.
But DHPOS makes me do the latter.
Is that what's intended cos it ain't quite right for the UK

OK, I can work around it by inputting the value of a £10 coupon as £8.51 I guess so it certainly isn't the end of the world...
Hmm...the more I think about this, it's an accountancy nightmare. Say I accept a manufacturer's coupon on a food product for £0.25. In the UK, food is zero rated ie there's no tax on it. Maybe I ought to look at allowing the employee to change tax at time of sale and setting the tax rate on all coupons at 0% - so the coupon is input at full face value. Then at the end of the day the company accountant would collect all the coupons together and do a manual tax computation and adjustment.
Just off to see whether that works.