I took my car in to check out what was making my tire lose pressure, and they immediately found a leak and quoted me on resealing it. They told me there might be damage to the steel inside since it had been driven while under-inflated.. when they took it off, though, they affirmed there had been no damage (rather than trying to upsell me on a new tire) and had it sealed / remounted for less than $20 in about an hour.