>>>>> My daughter actually made the decision today and signed a 3-year lease.
>>>>
>>>>A bit late now, but did you check out car-sharing?
>>>
>>>Ok, I googled 'car-sharing' and now know what you mean. No, my daughter wants/needs to have the car for any time and exclusively for her. Car-sharing is not for her.
>>
>>In the city of Vancouver, car sharing has almost tipped: https://www.ubyssey.ca/blog/ultimate-guide-car-sharing-vancouver/
>>
>>For low kms/year it's starting to look pretty attractive.
>
>I don't know what kind of kms/year my daughter will have but I don't think it will be high (probably less than 10,000 miles per year). But she needs the car for work; not just for some times. If I suggested to her a car-sharing, she would not take it well :)

from your OP: "Shopping for a car (helping one of my kids). "

One way to read it would be you are helping by paying for it (and compared to that, car-sharing ***is*** a let-down) or it could mean you assist by adding technical hints or add as a distraction while haggling with the dealer (and in this context, reminding her of car sharing options IMO is closer to due diligence).
My solution is to always offer #2 if asked, but in situations closer to #1 to always include the helped one in the financial part as well - at least 25% of cost. This way I am certain that value/price/effort considerations are learned, as early as possible...