Ugh. Yes, been there, felt that pain. One less in the world...
That is just egregious, and referencing the "when I bought it" price is such an eyeroll-inducing move.
I've become a "super high maintenance buyer" who asks sellers how they are going to be packaging whenever I think there's a chance this will happen. I offer to pay for extra costs if needed for it to arrive safely, and tell them not to worry about the shipping time - "better safe than fast". It annoys a few of them ("of course I will ship it well") but does seem to help avoid catastrophes. Some people are clueless tools, but some just don't have the knowledge or experience.
I snagged an awesome ImageWriter II in box and asked the lady about shipping. She was just going to ship it directly in the aged original packaging. She was more than happy to double-box it once I explained how that wouldn't be safe and sent
this link. She asked why people cared so much about the condition of vintage Mac stuff and I gave her an abbreviated spiel; she was very gracious, told me the items belonged to her late father and she was happy that they would be going to someone who would enjoy them. ("Selling my grandparent/parent/spouse's old stuff" is something I've encountered quite a bit.)