How to make a large custom-size cardboard box?

My goal is to make a cardboard box that has the very unconventional size of 70" x 20" x 12". It's for transporting a piece of furniture but we don't want it to be any larger than that. I couldn't really find any sellers who could make a custom-size box this big (unless you buy in bulk), except for FedEx who apparently will do any large size, but I think the price is pretty steep.

Despite my best efforts researching, the only solutions I found were to shrink a refrigerator box using typical box resizing methods, or to cut a refrigerator box into flat sheets that I then use to build a new box from scratch. But I'm not really sure what's the best way to go about either of these methods since my desired box is so big. Something like this looks good, but I'm not sure exactly how that box was assembled. Any tips? Thanks

The box shown in the linked video was just assembled with sticky tape.

A similar way would be to get a box that is over-size, cut it in 3 directions, into 8 sections (with one corner in each section) and reassemble it with the parts overlapping. The cardboard doesn't need re-folding, and suffers no strength loss because of it.

Leaving the last two sections to re-assemble. The completed box has all the original edges and corners intact. This is absolutely different to the video, where the guy cuts along the original edges. But it does need very good sticky tape, on both sides of every join.

Of course, if the box is already the right length in any direction, it doesn't need to be halved that way.