First off, if you want to market something like that, then the price will have to be fairly reasonable for most, unless all you want to do is high end installs. Next thing, they have to be built sturdy enough that a drawer full of tools won't bow the drawer and the bottom drop out. They will have to be way better built than the box store cabinets. Just like the cabinet build that Steevo did with the HF rollers. Can you build something sturdier than that for about the same price or less? If not, then most people will buy tool chest or rollers, remove the wheels, and add a top to it.
If you try to attract the higher end garages, you will still have to compete with the ones that will buy a half a dozen HF roller bases, or you will have to compete with the other garage cabinet guys that are already out there with the shiny, glossy cabinets in the color of your choice.
I'd really venture to say that it's not a very good market to get into if you plan on making a lot of money. If it were me, I'd spend some money on advertising. Advertise home interior cabinets like kitchen and bath, and throw it in there somewhere that you also do custom garage builds. But in doing so, you'll have to showcase a few places that you have already done to draw a persons interest. Then you will also have to factor in the one or two big questions......how strong are they and what about moisture problems? And don't tell someone that the cabinets that are already out there are MDF and yours is no different than theirs. That will just force a person to go buy one from Lowes or HD if your is just the same.