It is good you are hesitant. This place is not a "school" but a training centre, their stupid name says it all. 7000 RMB is quite low considering the amount of hours you will be working there, and China has become quite expensive.

Very often, training centre operators in China are crooks, and you should research them a bit better before you decide to sign up with them.

I suggest that:
1. you ask them to send you a copy of their license to hire foreigners. If they can't or would not send it, then you can be sure they are not legit.
2. you ask them to send you the necessary paperwork to apply for a Z visa (only that makes you work legally in China). Again, if they don't, you can be sure they are not legit.
3. you ask them to send you pics about the apartment they intend to put you in. Housing is very often a problem and sub-standard, so be very wary!

Good luck!

Mr T has hit the nail on the head.
This is the best advice you'll receive.
Also ask for contact details of past and current foreign teachers.
If you take the Job,make sure when you arrive you have access to enough money to "run for your life" if the school turns out to be a pack of lying *$%@#