Service tax voluntary compliance encouragement scheme

I am in Air Travel Business and having Some following Query Pls. reply Urgent....

A proprietor is engaged in the booking of the foll: 1)Buying air tickets from authorised IATA agents at discount and selling such tickets to his clients.The IATA agent charges ser.tax on basic fare to proprietor. IATA agent does not give any commission to prop. except discount on air tickets.The proprietor levies ser.tax and service charges of rs.200/- per ticket when he bills to his small client. Query:on what amt. is sub agent liable to ser.tax? Does he has to pay ser.tax charged and collected from his clients? Does he has to pay ser.tax on service charges of rs. 200/-collected from his client? 2)In the same way he books hotel rooms for his clients from Hotel owners directly or auth. agents.He charges his clients same way as he does in air ticket booking.What is his liability in sert.tax?