We generally don't charge on a per hour bases. We have tier level billing for most general repairs based on difficulty and the time needed to complete the repair.
We generally don't know how long a repair will be until we diagnose the problem with your device and the extent of damage. However, we will give a rough estimate of time as best as we can.
We do charge for parts and some components depending on the type of repair being performed. We'll let you know upfront what that cost is before the repair is started though.
We have a 90 day warranty on all labor and parts for any of our repairs. Of course this is limited to only the repair that we performed. As with all devices parts wear out one by one and we can only warranty what we worked on.