Major thing that needs to be considered is the location and size of the damage. If damage is at the edge of the windshield then it will spread fast and will destroy the integrity of the glass. If any edge damage is found then front window repair it soon. It will save the life of your windshield.
Insurance may cover for the partial cost of repair and replacement. So, the cost can be a little offset. Ideally, you should deal with service oriented car glass shop so they can give you a free estimate, lifetime warranty and insurance paperwork assistance.
If the chip is smaller than a quarter and the crack is less than 12 inches long, they would most likely provide service to you at the convenience of your home. The repair kit they will be bringing will contain several materials, tools and equipment. This would include a windshield repair bridge that is self-leveling and is able to reach anywhere on the windshield together with the injector. A crack expander that slides easily and reaches low on the windshield. An A.C. powered ultraviolet curing lamp and a 15 watt, 22 inches bulb for curing long cracks. A drill if the chip needs to be cleaned. A curing film that enhances the ultraviolet rays for faster and complete curing, a UV protected syringes designed to protect the resin from the sun's ultra violet rays, the resin and some other stuff.
On most car windows there is a small triangle printed from the manufacturer. Under the fix auto glass repair serial number is a small point with a number. This is the year of manufacture of the window. With popular car models this figure represents the model year. For example a 7 would indicate a model from 1997. If one window has an alternative number it may mean that the window has been replaced due chip or crack damage (windshield) or burglary (side window). If the windshield and side window have a different number from the rest of the windows, this could mean that the car has had a collision. Due to damage the windows have been replaced.
If a rock hits your windshield while you are driving when it is already cracked, this can cause it to shatter too and you will not be able to see the road. Dings and scratches generally won't do this but there is always that risk factor that you have to be cautious about.
Most of the technicians have years of experience and are capable of undertaking any type of repairs. Usually they are professionals and not the general car mechanic who lacks expertise on this matter. It all depends on the kind of service provider you are going to. Make sure, it is a reputed one. The glasses of doors, windshields and mirrors can be mended by the skills of the workmen. Some of them are mended so well, that it would be difficult to say that they were once broken. A cracked mirror is said to bring bad luck. So don't have one in your home if you believe in this. Instead get it mended and restore it to its former glory.
If you have a chip or a growing crack in your auto glass then the best time to get it taken care of is immediately. Every heavy gust of wind or debris that strikes your window can cause a large and sudden streak in a crack that forces it to spread. Tend to your windshield and get the crack taken care of immediately.