How to determine value of a Persian Handmade Carpet and the important features to look out for

Valuing a hand knotted rug is not an easy task. It needs in-depth knowledge of different types of carpet and the current market value. However, some basic pointers can help you better understand what aspects of handmade rugs are important in this process.
I have tried to explain some basic points that do not need expertise, to help understand the value of a Handmade carpet. These are some essential points that help determine the value.