Something like Dwalt Tstak, Magnusson Stakkur or Stanley FatMax sorta thing that can be expanded as and when needed was my first thought?
See also Bosch/Sortimo Lboxx. The 102 is a good depth and they stack, get some shadow foam in there and you’re sorted. They do blanks for all the common stackers.
Don’t be tempted by the deep and cheap Stanley roller units, the top box is okay but it’s a pain for trying to find tools as it’s so deep and doesn’t connect onto the bottom well. For amateur use it’s fine but would get old quick if you’re lugging it about as a daily.