Each time you select a professional to hire, there are some things you should always do before actually hiring people. You have to do some due diligence to find out whether or not that individual actually is a expert to get started.
Verify some credentials, see if they have a portfolio and get some references. No matter how good the person may look or appear or sound or anything that may be, it's important that you find out more about the candidates who want to do business with.
You can also find experts for garage door sales and installation in NJ at all day garage doors. There are plenty of potential candidates to choose from, but as usual there are some scams that prey on the ignorant just to make money quickly and in turn damage to the rest of us.
Things to consider before doing any kind of business with anyone who you have never worked with before is to first verify the legitimacy or their claims.
How long as the company been in business? Do they make promises or claims in their advertisements that can be strengthened? Also, how multifaceted they? Can they handle all the work themselves or they are limited in their abilities? Do they have client testimonials that you can verify?
You can find out about them online by searching Google or other search related either to their company name, personal name or through generic search terms related to their industry?