New insulated and two-car doors, with struts for wide doors on open lots.
This site's price table gives $1,595 to $2,850.
It is a steel brace across one section that stops the panel from flexing and bowing.
On a garage attached to the house, it generally earns its keep.
It might. Ask about allowed styles and colors before you order.
No. Taking it down and away is part of the price.