You’ve got the plan in your head—get a container, add doors, windows, or other simple improvements, and then you have your container office, shop or cabin. You’re handy, know your way around a do-it-yourself project, but where to start?

No need to reinvent the wheel—container modification kits will come with everything you need to install a door, window, partition, AC, insulation or even a sky light. See the pictures below for ideas. You provide only the cutting and welding skills.

You configure the kits that suit your plans. The basics include a lockbox, man-door (steel, 3 feet wide), a roll-up door (6', 7' or 8' wide), windows, insulation, AC with a cage, etc. Order them from your friendly container store (Super Cubes has all the kits and free DIY support).

Cut a hole in the container to the size noted in the instructions. (Tip: Borrow or rent a plasma cutter, which whirs though steel using only air and electricity.) Install the door, window, skylight, or whatever.

Kits take all the guesswork out of framing a wind- and water-tight add-on into your container. Container kits also solve problems you might not have considered. For example, the AC kit comes with a frame, air conditioner, and a cage to weld over the AC so that no one could pull it out and potentially gain access to your container.

With kits providing everything you need, you can have exactly the container office, shop, or cabin you imagine—foolproof and frustration-free.