The average home mechanic can change his own brake pads, but the task takes about an hour. The task is more complex than other vehicle maintenance tasks. The primary expense for doing the job is the cost of replacement brake pads.
To access the brake pads, loosen the wheel lug nuts, jack up the car and remove the wheel and tire. Remove the bolts that hold the caliper in place and slide it from the disc. Use a bungee cord to hold the caliper assembly so it does not hang from the brake line. Remove the old pads, open the caliper with a C-clamp and install the new pads. Bolt the caliper back in place, test the brake pressure and reattach the wheel.