Dealing with unruly, frizzy hair is just about as fun as getting a root canal, except the root canal stops when the procedure is finished. The hair? That just seems to get harder to cope with as time goes on. So it's no wonder that keratin-based straightening treatments are a hit at salons around the world since they tame even the wildest of locks for months. The problem is, they can be pricey - ranging from $150 to $300 in some cities.