If you've installed a replacement door or two around your home, it seems pretty simple -- all it takes is tightening a couple of screws and you're done. Installing the largest door in your house, however, is not quite so simple. Garage door installation, whether manual or automatic, can be difficult and dangerous. Manual garage door installation is much easier than automatic garage door installation, but the one you choose generally depends on what kind of door you have.
To install a single new garage door it should cost between $500 and $800. They demonstrate that the average homeowner can usually tackle such a project in a nine hour time span and a professional will be able to complete it in roughly five hours. Should it be a DIY project? Not really, most housing experts point out that it is a two-person job, requires advanced carpentry skills, and even knowledge of household electronic systems.
If the door goes up but goes down only when you hold down the wall switch, check to see that the safety sensors are in alignment. The small light on each sensor should be lit up when nothing is between them. Door sensors do go bad, so if no light is showing at all, you may need to replace them. You can save yourself some time by using the existing wires. Also, direct sunlight shining on sensor eyes can make them misbehave.