We adopted a senior little poodle/terrier mix from the local dog pound.
Our Vet felt by looking at her teeth etc. she was around
13 years old. We were blessed to have her for another
5 years. So she was approx. 17-18 yrs old I guess.

Other than Scruffy, our longest living dog lived
to the age of 12.5 and she was a GSD/lab mix and
my favorite dog of all time.
(I still miss all my past dogs.)