The cost of removing activation lock at an Apple Store depends on the type of device and its condition. If the device is still under warranty or AppleCare protection, the service may be free of charge. However, if the device is out of warranty, the cost can vary from $29 to $129. It is always recommended to visit an Apple Store or contact Apple support for a personalized quote and to ensure that the service is done safely and securely. Additionally, it is important to note that activation lock can only be removed when you have proof of ownership and present the device at an authorized location.