I was told I needed a new coil pack, new sparkplugs and sparkplug wires for my V6 F150 and quoted $735.
The plugs and wires had already just been replaced and had only done 890 miles.
I bought a high quality coil pack for $105 retail and installed it myself in thirteen and a half minutes. (You can buy a new coil pack for as little as $48) Even if I had required new plugs and wires, quality products would cost $70 total.
Even if they had replaced everything they wanted to it would have been an hours labor. Which means they are charging $560 per hour.
The story is actually much worse and not isolated but you get the idea.