How Much Did It Cost to Install French Doors? -- Reader Intelligence Request

(Image credit: pics721/Shutterstock) We regularly ask readers to share their experiences with various household activities and home projects. We hope this collective information proves helpful to anyone needing to get a basic sense of how much certain items cost, how much you can expect to pay for a service, how long a project takes, or how often you should be doing something. Today's Question: How Much Does It Cost to Install French Doors?