How to find the Reference product for an Iobject

Hi Experts,

I have the below requirment, kindly help me on this.

1. Need to find the reference products attached to an Iobject

2. Then I need to get the service hierachy for the resulted Product got from step 1

3. Then I need the renual transaction number for the resulted product got from step 1.

let me know the tables or FM to satisfy the requirment.

Thanks