> You should own your own custom-fitted boots though

I would preach this with snowboard boots (+ helmet), made travel easier as well when you live nowhere near snow. Trying to take up skiing now and have no idea why I didn't think to do this with ski boots. Would probably help, a lot.

As for rentals it's easy to avoid beat-up janky gear. Have to go places just outside the ski town areas. Usually have to find a shop outside the resort for snowboards if you bring your own boots anyway, but easier to find better gear options. I remember getting a new (or basically new) K2 board from a general sports store in Reno, same for getting rentals in Queenstown or Denver or Vancouver before hopping on a bus.

Shops outside the resorts tend to have reasonably priced demo rentals, newer high end gear they are hoping you buy afterwards. Far better equipment that is nicely tuned than anything the resorts offer.

Not paying the oversize/ski baggage fee and lugging that gear around the whole trip while having quality rentals available levels the rent vs buy equation -- if buying a season lift pass makes sense so does buying your own gear, otherwise it's more hassle than it needs to be, imo.