Only cars I'd see going for 35k have much higher miles, have been in a major front end collision or are salvage. I'd say 43k with some of the service completed. Is mismatched tires that big of a deal? I know it's not ideal by any stretch but wasn't thinking it's the end of the world either.

 

To me a mismatched tire shows 1 of 2 things.

Innocent - it got a flat where a correct tire could not be sourced and put on whatever fit right.

Bad - Owner didn't care enough to make sure to get a tire that matched.

You do not want tires with different sidewall and grip properties on opposite corners.