We do tires at our shop. We got a great deal on some used machines. We are in a high traffic area so we get a lot of walk in business for people with flats, etc. It's an added bonus to be able to offer tires to our customers instead of losing the business to someone else. We just hooked up with a new vendor for tires and we really make a decent profit on tires. We don't stock tires so they need to be done on an appointment basis. I think the profit is worth the investment in the machines.
Having a the ability to balance tires in house is a huge plus. A lot of our customers issues can be solved with just a re-balancing of their existing tires and it's great to be able to do that for them rather than send them elsewhere.