If you are looking to setup trade allowance management then one thing you will do is create a grouping mechanism called the customer category hierarchy. This allows you do define a tree structure of categories to assigned customers. One you have done this it will help you find customer when you setup a trade allowance agreement or fund. The adding customers is manual it’s worth planning out ahead if you want a lot of hierarchies or a couple based on customer grouping. The thing to keep in mind is that with a trade allowance agreement you can switch the hierarchies and find the customer you want to add to that agreement. The fund is different if you want to use that to allocate a budget you can only pick from one hierarchy.
Here is a quick overview.
AX2012 R3 CU11
If you are looking for a D365 overview you can find it here.