The shop has set prices on labor for any given job. The $200 price for pads and labor is going to be about right for having them put it in and supply your pads. If it's a cool shop, you can try to sweet talk them into lowering the price, but if you've already paid for it, I don't think they'll change it. Next time, buy your own pads and do it yourself or get that guy that offered a price of $50 to do it for you. Brake pad replacement is easy. You would save a lot of money if you learn to do at least the simple maintenance on your car like brake pads, rotors, oil, coolant, plugs, and stuff like that. Good luck.