If you're doing a RT to and from the same destination, and have a place to store your box, then there are always plastic boxes available.

They show up on Craigslist from time to time, and presumably can be re-sold.

https://eugene.craigslist.org/bop/d/...462323877.html

Of course that is less convenient if you are doing a multi-point trip, or have no place to store stuff.

I've bought a few bikes on E-Bay. One came in an extra fat box that parts were strapped down inside. I may still have the box laying around here somewhere. The bike came to me in good shape, but I still would have preferred that the seller had invested in some foam pipe wrap, and isolated the parts better.

Keep in mind that S&S coupled bikes, or folding bikes (Bike Friday) may save on shipping costs, but would have a higher up-front cost.