Work Permit and Visa

Hello. I have a single entry three month visa which expires on November 16. I am looking for work as an English teacher but many of the better jobs require a work permit. Can your organization help me to get a work permit? Please tell me all the requirements for the work permit.

If I cannot get a work permit at this time, what is my next best option for getting the longest term visa available and does it require any additional documents that I submitted to get my original three month single entry visa?

Please include your fees for your help and explanation of why using your service might save me the time and trouble of physically having to leave Vietnam and then apply for a new visa to re-enter Vietnam. (I suspect that is likely the way it has to be done but I am hoping that if I pay an administrative fee, there is a way I won't have to make such a trip.)

If you cannot help me defray such a border crossing trip, what are the advantages of using your service?