Hello I will help you with your question,
It may be a blown fuse or the blower resistor rather than the blower motor but if you have or can get a 12 volt test light I can help you to test and see.
Would you like to do that?
OK hoping that they diagnosed it correctly you will have to remove the rear quarter trim then there is one electrical connector and three screws to remove.
Click here for the blower removal
I don't have instructions for the left rear trim but it is not hard to remove, just find the fasteners and remove them