Several companies make sliding trays for your storage compartments. This challenge I see in the purchased ones is the price, they are expense.
I made this one for about $40.00. When you purchase the draw slides be sure you get the 100% extension models. I used simple plastic storage containers. The simple box style and the draw style boxes you can get at Walmart.
The containers are strapped down with one inch nylon straps with buckles I got at REI.
The slide is hinged so you can get to the area below the slide.
This screen door lock keeps the slide locked in place.