The Milwaukee Packout Dolly Multi-Purpose Utility Tool Cart costs $99. Meanwhile, the Ryobi Link Modular Dolly Multi-Purpose ...

The Packout Rolling Modular Tool Box is a dolly base that allows owners to simply move the rest of their Packout stack, supporting up to 250 pounds. It’s available at Home Depot for $139 ...

This is why any good Packout stack should start with the Rolling Tool Chest. Of course, it wouldn't be very efficient to get a huge rolling chest if you're only going to use it as a rolling dolly.