Opening a Madrasah in the Musjid

Q: Can an ustaad teach hifz in a masjid when he dose not receive payment directly from the students but the students pay madressa fee's to the community who run the masjid and then the community pays the ustaad?

Q: Is it permissible to teach in the masjid and take a wage? If it is not permissible, does this apply only within the boundary or outside as well? Does this apply if an ustaadh is given permission by the mutawalis as well?