Loop through tables to get all possible combinations

I have a simple model but complex request. Below is the simplified version of the model.

In Table1, we have list of units and parts that go into those units. In Table2, we have vehicles where those parts are installed. And in Table3, we have population of those vehicles.

The request that I received is that the user wants to get summarized population but based on expanded logic. First, when user selects Unit ID, they should see all parts that go into that unit and vehicles where those parts are installed. In following columns, they want to continue expanding this table by adding all units that are installed in those vehicles (not just the originally selected unit), get related parts to those units, and again lookup vehicles where those parts are installed. This table would expand until all possible units and parts are listed and then population would be shown in the last column.

I am not sure if this makes sense but if not, I would be happy to elaborate further with examples.

Any suggestions on what approach to take in order to come up with such summary?