Replacing a garage door opener is a last resort, when other repair efforts fail. Make sure you have checked the previous repair steps before you commit to a new door operator.
Not your problem? See 'Garage Door Opener Problems' and 'Overhead Garage Door Repair' for all the garage door topics.
Garage door openers made prior to 1993 do not meet current safety standards. You may find it difficult to find parts or information for openers that are older than that. If this is your situation, replacing the garage door opener may be a good move. You can get a new garage door opener from a home supply store for about $150 to $200.
There are different types and styles of openers and of course features that cost extra. For a garage door that already has an opener, you may be able to re-use some of the wiring and the hangers for the unit. Installing a new unit is a fairly big job and will take two to four hours if it goes well. Longer if it doesn't go so great.
Set up a table to work on and follow the instructions that come with the unit. Take your time and get some help when you need it. With a little patience you can have a new garage door opener installed in an afternoon. Your garage door opener problems are over.