Apple repairs are expensive because they dont actually repair anything - they just replace the entire part.
For example if the logic board has suffered liquid damage they quote for replacing the logic board. Did you know Apple will never quote the repair price over the telephone! They insist you visit the store and have the device inspected. That way when they tell you how much to fix it and that it is as much or more than the costs of a new device they have you in the store to dazzle you with the new device.
Even when you have a crack in your screen they insist you visit the store for the device to be inspected! They dont want to tell you how much a screen replacement is because they don't want you to shop around!