Getting events and tracking multiple objects in ARFoundation

Hello,
I am having a bit of trouble with understanding the ARFoundation API.
Unlike the ARKit 2 API, which is nice and cozy, I don't get where I'm supposed to get to get any info about anything. If you could point me in the right direction, I'd be grateful forever (or for a year at least!)

To start with. I need to track 4 different objects (i've got ARObjects from the Apple App) in a room and instantiate 4 different prefabs. How do I do that? Do I need multiple AR Sessions? Multiple Session Origins? Multiple TrackedObjectManagers?

Then. I want to get the instantiated prefab. I couldn't even find the place in the API where it is being instantiated. Where can I get that?

So. Now, where can I subscribe to the events of the tracked objects? I'd like to update the instantiated GameObject each time when the tracked Object is being moved. Can I get a) an event, and b) the delta.position or something from the tracked object?

I want to achieve something pretty simple. With the ARKit 2 sample projects from bitbucket, it worked perfectly - and I understood the code. I am now searching for the equivalents of it in ARFoundation. I haven't found any good example projects or answers for my questions in the documentation. I'm pretty lost.

Can you point me to the right directions? Thanks <3

Below is the arkit2 code, just for reference to what I mean.

Code (CSharp):

1. // CODE FROM ARKIT 2
2. // This is so simple, I love it. What are the equivalents of this in ARFoundation.
3.  
4.     [SerializeField]
5.     private ARReferenceObjectAsset referenceObjectAsset;
6.  
7.     [SerializeField]
8.     private GameObject prefabToGenerate;
9.  
10.     private GameObject objectAnchorGO;
11.  
12.     // THOSE EVENTS
13.     void Start () {
14.         UnityARSessionNativeInterface.ARObjectAnchorAddedEvent += AddObjectAnchor;
15.         UnityARSessionNativeInterface.ARObjectAnchorUpdatedEvent += UpdateObjectAnchor;
16.         UnityARSessionNativeInterface.ARObjectAnchorRemovedEvent += RemoveObjectAnchor;
17.  
18.     }
19.  
20.     void AddObjectAnchor(ARObjectAnchor arObjectAnchor)
21.     {
22.         Debug.Log ("object anchor added");
23.         if (arObjectAnchor.referenceObjectName == referenceObjectAsset.objectName) {
24.             Vector3 position = UnityARMatrixOps.GetPosition (arObjectAnchor.transform);
25.             Quaternion rotation = UnityARMatrixOps.GetRotation (arObjectAnchor.transform);
26.  
27.             // THIS REFERENCE
28.             objectAnchorGO = Instantiate<GameObject> (prefabToGenerate, position, rotation);
29.         }
30.     }
31.  
32.     //THIS
33.     void UpdateObjectAnchor(ARObjectAnchor arObjectAnchor)
34.     {
35.         Debug.Log ("object anchor updated");
36.         if (arObjectAnchor.referenceObjectName == referenceObjectAsset.objectName) {
37.             objectAnchorGO.transform.position = UnityARMatrixOps.GetPosition (arObjectAnchor.transform);
38.             objectAnchorGO.transform.rotation = UnityARMatrixOps.GetRotation (arObjectAnchor.transform);
39.         }
40.  
41.     }