You can observe the operation of your vehicle yourself, either by the indications on the panel, or by simple manual inspection. Among the statements below, it is correct to state that:
items, such as windshield wiper blades, only a qualified professional will be able to check if there is a need to change them
the tire must have grooves at least 2.6 millimeters deep
stains on the floor, under the vehicle, it means that there is brake fluid leakage
every 20.000 km, the state of the sails must be checked