Even if you do have to get the entire windshield replaced, you could still get off the hook if your insurance company will cover it. Free chip front window repair is included in a lot of policies, so check this out. Just remember that insurance providers often have stipulations about which glass company you are allowed to go with, and therefore you will probably have to use a company they suggest.

The next morning, we woke to a heavy, hot task of cleaning up the mess of limbs and leaves. We surveyed the damage. Fortunately, the heavy tree missed our carport by a foot. And only a few boards on the wooden fence needed to be replaced. It would be a fairly simple repair job. Next we moved onto the task of clearing away the fallen branches. Rick used his chainsaw to cut limbs into manageable sizes. I raked limbs and leaves into a wheelbarrow. Everything was neatly arranged in a pile in the front of our home for pick up.
Now open the windshield car auto glass repair kit, it contains an adhesive disc. Place it in the middle of the chip and the disc's tab must be pointing towards you. The pedestal from the kit has to be placed on the tab.
If you are not sure where to find props in your area contact a windshield chip repair stylist or browse antique stores and auction centres for a wide selection of interesting pieces.
Another way to figure out ARV is to get an appraisal from a certified appraiser. Yes this costs money, but if everything else looks good about the deal and you are uncomfortable with the realtor's comps, you can always get the opinion of another professional. They go more in-depth when appraising properties then realtors might. However I only trust the appraisal when I actually hired the appraiser. This way I know that I have given him/her the instructions on how I want the appraisal to be completed.
Most auto glass companies offer a lifetime warranty which proves that the process is reliable and can be trusted to keep you from having to replace the entire windshield.