At what age will car rental not be possible?

hi, here is what I found...https://www.smartertravel.com/2010/03/29/know-your-rental-car-age-restrictions-in-europe/

It varies by country, some my impose an age penalty, others may not rent to you past a certain age.

I once heard a woman " too old" to rent a car in France, and she was staying about a month or two so she LEASED a CAR, which by law is allowed in France at just about any age! Viva la old brains! :)

In the same vein what is the "minimum" age of rental? Is it 21? If so why can't it be 18 or even 16? Perhaps there's a rationality behind age limits/cutoffs? I don't think it's wise to try to circumvent upper/lower age limits because it's probably in place for a good reason.

Since most European countries do not issue drivers licenses until the age of 18, there is a very good reason not to rent to 16-year old's.

I don't know about rental company limits but Italy places no age limits except that the validity time varies and license must be renewed at different intervals according to age group:
Up to 50 yr old - every 10 years
From 50 to 70- every 5 years
From 70 to 80 - every 3 years
Over 80- every 2 years.

It is some rental companies that have age limits, not countries. I've rented in France, Italy, Croatia, Greece, and Slovenia when over 70.

It depends on the rental company. I am going to Spain and France with my parents in a month, and booked a rental through AutoEurope. Our actual rental company will be Avis, and they have no upper age limit (which makes my father happy, as he's 80 and is reluctant to let me do all the driving).