Steel entry doors - when a garage is being fitted with new doors, it is also a good idea to consider a separate single 3x68 exterior door with half-glass and locksets too. These may require some carpentry, but they are a good way to allow for some flexibility in the choice of larger garage door, and can ensure that the homeowner will have more than a single way in or out of the structure. The average costs for such a feature range from $250 to $1000 each.
I'm not a professional, but I watched as my garage doors were serviced last year. The tech used a spray lubricant (I had bought a different brand in the garage door section of a home improvement store). He sprayed the inside of the entire track, top and bottom, the rollers that ride along the track, and all hinges on the door. He sprayed each hinge twice -- once on each side. The techs were more generous with the lubricant than I was when I'd done it before, so don't be afraid to give it a good squirt.
They sent Doug Fussell out to my house on the day after Christmas! I had only called them three days before! Doug was a premier technician, very thorough and very efficient. I expected him to take two days, since he was replacing two doors and adding openers on each door. He only took the daylight hours of one day! I could not believe how fast he was! In addition, he thoroughly taught me how to use the remote openers. I highly recommend them to anyone!