Testers as addition to customer order

[NoOneLt]

Hello guys, need to solve few problems:

• Want to allow customers to add 1 tester per 20 EUR in order, tester is a product tester, can be a simple item. I dont think it can be implemented in standard though...
• Next ide is to relate testers category to all products in bundle, while i have around 300 of them i can not find easy way to do it in bulk, i it true?

Maybe someone would have another solution?

BR and thanks!

[Jörgen]

If I remember correctly, AwoCoupon is the solution for this. Check with https://awodev.com/products/joomla/awocoupon
I am not affiliated, I just use the extension.

Jörgen