Most chain shops offer a very low cost tire rotation. This is especially true of chain tire shops. On the average, you shouldn’t be charged much more than $20. This is because a tire rotation shouldn’t take more than ten minutes at the most. A tire alignment, on the other hand, is a job that can take as much as a full hour to complete. For this reason, most specialty tire shops and chain shops like Wal-Mart and Pep Boys will charge around $50 for a one time alignment, and usually around $90 for a lifetime alignment. A lifetime alignment is a contract wherein you can bring your car in for a seemingly unlimited number of alignments once you’ve paid the initial cost. Sometimes you will be limited to the lifetime of the tires. Other times, to how long you own the car.
For more info, see Is Tire Alignment Worth the Cost