Where is the best place to buy replacement car tires?

My son ran over something that trashed the inside sidewall of his front tire which means it is irreparable and time for a new tire. All the tires are 80% worn which means it’s time for 4 new tires. Here is the conundrum. Tires need to be rotated and many tire dealers offer free rotations which is crucial to longevity of tires and what my son is looking for.

He goes to school 250 miles away from home…travels to and fro and is in many places at many times and he is looking for the best tire dealer with quality tires first and foremost that has the most AND the best service locations that will honor the free rotations again depending on where he will be. We are talking a large late model sedan that he intends to drive the next 20 years or forever as he loves this car.