We are interested in an outdoor living space. Has anyone got any idea what an porch would cost?

We would like to have the concrete poured and have a roof. Similar to a sunroom. It would be roughly the size of a one car garage. Anyone have a rough idea of what this would cost? Actually it would only need a roof and two sides as it would abut the wall to the house and the wall to the detached garage. We are in Florida if that helps...any ideas about cost?