If you want to check the warranty status on your Mac, you can check it with your Mac's serial number at the following address: selfsolve.apple.com.

Apple covers only the hardware (physical parts). If you have a hardware problem with a machine in warranty, you can get if fixed at no cost (includes the part and the install by a technician).
Any software-related issue will not be covered by Apple, meaning you will have to pay to get it fixed.
All is described in Apple Repair Terms and Conditions.
I can come at your home ($15) and fix it. Usually software issues are fixed within 1h ($30), if not, then I will give you an estimate of how long it should take (cost) to fix it.
However, if you are subscribed to the Applecare Protection Plan, you just need to contact Apple and they will troubleshoot your software issue with you over the phone.
Troubleshooting a software issue, over the phone, can get really complicated ! You may spend hours trying to understand what the Applecare guy needs you to do and, sometimes, since they are not in front of the machine, they may miss some important clues. This is where I can help you and save you time and effort for only a few dollars.
I can come at your home ($15) and see what is exactly wrong. Then, usually within 1h ($30), I give you an estimate on the cost of the repair.
In general, for hardware repairs, count between 1 and 2 hours ($30 or $60) for the labour and part costs vary (from $20 up).
Basically, for 1h (30$), I can either fix your software issue or estimate what would be the cost of the hardware repairs.
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