It is very possible but then that system is not for you. These systems are incredibly complex already and while there will always be some customization you should question yourself if this is where your competitive advantage is?

Is Lidl earning more money than their competitors because they base their inventory management system on purchase prices while others do not? Then build/buy a system that handles that and it could very well be worth it if you look at the business case

But if it is like that because that is how we started out and we cannot quantify how much better it is...then maybe you should just change your process.

But very unwise for choosing SAP. Should have spent 500M on something that fit their needs.