Most of the time, the reason why locksmiths charge a lot for their service is because of the clients’ urgency. If you need to change your locks immediately and outside the usual business hours, you may expect to pay more for the service. Along with this, locksmiths may also charge more if they have to travel a distance to get to you.
Generally, locksmiths charge per hour. For changing a Yale rim cylinder, you can expect to pay around £65 on average to upwards of £95 for the job. If the case needs changed, this will cost more.
If you have a passion for DIY projects, you can also try to change your Yale rim cylinder yourself. This will save you the cost of the labor and this will also allow you to buy replacement parts from cheaper sources.