As a Chinese foreign trade enterprise officer who has already worked in Sunflower English Education Centre, Suzhou for many years, I have already skimmed quite a lot of posts on ESL Teachers Board carefully. I consider that the main reasons cause these problems and misunderstandings which mentioned in a lot of posts are cultural gaps and asymmetry of information. In fact, there exists clear policies and content from Chinese government department to lead foreigners to achieve the working permit as a legal ESL teacher. Now, just allow me to make a brief introduction for anyone who may concern.

Q1: Which kind of company could recruit an ESL-teacher?
A1: The companies which own the qualification identified from local government of recruiting foreign experts of culture and education type.
Relevant Website Link1:
http://www.safea.gov.cn/content.shtml?id=12744214

Q2: How many qualifications a foreigner needs to satisfy if he/she wants to become an ESL teacher in China? (We will raise an example of Jiang Su Province Administration of Foreign Experts Affairs, China in the following answer.)
A2: 1. Native English Speaker（USA, UK, Ireland, Canada, New Zealand and Australia）Of course, it does not include the special situations.
2. Degree and TEFL/TESOL/CELTA
3. At least 2 years work experience since passing degree(experience in an educational environment: with kids is preferred.)
4. If you don’t have 2 years work experience until now, you could go to Beijing to get Chinese Official International TEFL certificate, then you will also be suitable.
5. Clean Police Record
6. 12 month signed contract
7. Reference letter from last job
8. Committed and Professional Teacher
Relevant Website Link2:
http://www.safea.gov.cn/content.shtml?id=12744213

Q3: Why you may hear the different information about applying for working permit in China?
A3: The information is from your friends and family relatives, however, I am afraid that they may not be so professional about the relevant application procedure. Most of news they told you is obviously not from the official channels. Therefore, it is possible that cause misunderstanding between recruiters and employee.

Q4: How many kinds of visa are there in China? Which kind of visa you need to own to have the legal work permit to be an ESL teacher in China?
A4: D-visa: the foreigners who will settle in China.

Z-visa: the foreigners who will work in China and his/her accompany family members.

X-visa: the foreigners who will study and have internship more than 6 months in China.

F-visa: the foreigners who will own invitation to do business, teach, have communication of science culture, have internship and inspect etc. less than 6 months.

L-visa: the foreigners who will travel or visit family relatives.

G-visa: the foreigners who transit the border via China.

C-visa: the foreigners who work as crew on international airplanes and trains, and his /her accompany family relatives.

J-1&J-2 visa: the foreign journalists who are resident in China& the foreign journalists who are temporary in China.

If you want to be an legal ESL teacher in China, the type of visa you should apply for is: Z-visa! The rest of type of the visa is all useless.
Relevant Website Link 3:
http://www.gov.cn/banshi/2005-05/26/content_1300.htm

We are going to continue updating the relevant passages soon, if you are interested in, please keep following us. Besides, we are delighted to offer the translation to the website links which mentioned above.