Best way to achieve a repeater within a repeater?


I am trying to build a repeater within a repeater. I have seen that if you build a custom module with a repeater, the variable for the loop gets appended, and there is no way to dynamically change it, so hubl modules are the way to go. The problem I am having is when you lay out the code within a hubl template, you end up with the internal repeater not being unique, so you can only set one loop variable. The easiest way to describe what I want to accomplish would be an ecommerce category listing: a header on left column with a description, and a description module in the right column. The whole module I want to build will allow our marketers to determine the number of categories for the left column, and number of detail modules separately for each of the categories set in the left column. Example, 3 categories left column, first category has 4 items, 2nd category has 6, 3rd category has 2.

To be clear, this is not for ecommerce but would function very similarly to that analogy.