What are the duties of an Imam according to Shariah, the Masjid Committee, and the Mutawalli Sahib?

In our local Masjid an Imam is appointed and there are some terms and conditions of the committee which is to be followed. Our Masjid is situated at semi rural area (Basti) of Kolkata. One of the terms is that the Imam should not do any work outside the look after and service of the mosque at the time when he is at service of the mosque as he is given a fixed salary (including food and shelter free of cost) for these purposes. Holidays given to the Imam is 4 days in a month during stay at home (journey for departure and arrival count extra days) but he always has more holidays than the holidays allocated by the Masjid Committee. The income of our mosque comes from two sources: (1) Rent money received from Handi (Deg). (2) Amount received on Friday during Jumuah, Asr and Maghrib time. The service includes: Five times salah, teaching local and poor children free of cost, teaching, discussion about Shariah, sharing the knowledge of Islam to uneducated and educated people, maintaining ledger of rent of Handi (Deg), look after the mosque. But he denied to follow the term and condition of the Masjid Committee. He is showing argument that the duty of an Imam according to Shariah is to only do the 5 times salah after the five time salah he can do any work (the work can be private tuition, business, or any work for money or for his personal requirement though for personal requirement the committee has never objected). I want to know the duty of an Imam according to Shariah and duty of committee member of the Masjid and the duty of the mutawalli sahib.