When your garage door starts acting up, more often than not it is telling you it's time to do a bit of maintenance. So, before hitting the panic button, try these simple repairs. First, examine the rollers and tracks. If you can't remember the last time you cleaned them (and they look the part!), give them a good brushing and then add some lubricant. Next, perform these simple garage door maintenance tasks.
You might genuinely need some extra parts when you thought you simply needed a broken spring replaced, and a good serviceman will perform a simple inspection to identify such parts. Nor is it unreasonable for a business to charge separately for a service call versus repair work actually performed. But the best protection for you as a buyer, being somewhat at the mercy of whomever you decide to bring on site, is to understand what is being done, and ask intelligently for a clear explanation or demonstration of why extra parts are required.