I read a book titled 国际商务汉语 by 李忆民, and I come upon 贵方 in one of the conversation reading. My questions are:

1. How common is 贵方 being used in real life conversation？[especially in business or organization case]
2. How polite is it compared to 您?

Here is one of them:  

I read a book titled 国际商务汉语 by 李忆民, and I came upon 贵方 in one of the conversation reading. My questions are:

1. How common is 贵方 being used in real-life conversation？[especially in business or organization case]
2. How polite is it compared to 您?

Here is one of them: