Recently traded in my 3 year old EX with a main Honda dealer. . A bit above average mileage , 27K miles. I was quite pleased it was considered good enough to include in their own used car stock. Interesting to compare its price against their other 3 year old Jazz. (They had several - Jazzes , Jazzi ?)
Their asking price was about £1000 higher than I got in part exchange. Fair enough I think , although I did concentrate the deal on a good trade in value, which would have reduced any other discount that may have been possible . You cant have both.
A Crosstar, same age and almost identical mileage was £1000 more. It would have been £1000 more when new. An SR model same age but with only 11K miles was only a couple of hundred cheaper than my EX. ( It would have been about £1500 cheaper when new. ) Or in other words my EX was about £1200 cheaper than it might have been because of its extra 16000 miles. In theory using my car more cost me £1200 . Although a doubt the SR owner got the full £1200 extra in part exchange.
But most interesting was an EX the same age as mine but with only 3K miles. They were asking £2000 more than mine for the privilege of its very low mileage.

(did the seller benefit fully? )
I can see the appeal of a car with 3000 miles rather than paying significantly more for a brand new one.
But if they bought mine , kept it 3 years and did the national average of 8000 miles per year it would still only be 27K +24K ,total 51K miles. Barely run in for a Jazz. And many Jazz owners do far fewer miles than this. Or do you pay £2000 more for only 3K + 24K miles, total 27K at 6 years old . Nice , but it will still be a 6 year old car that has seen 6 winters. etc. Will it still fetch anywhere near £2K more when sold?
Or do you buy an SR with 11k miles for similar money to mine but forego heated seats and warm bums?