Hi Durga,
I beleive the package that your friend has got is a decent one as far as starters are considered in Dubai.
The expenses with family will get upto 8000 AED(Dirhams) in Dubai.
The suggestion I can provide is that he can first move into Dubai leaving his family in India for a while, sort out the accomodation and transportation by himself and during this process if he arranges to find a shared accomodation which is the normal process in Dubai he will get an idea about expenditure and will manage to save some funds before he gets his family there. Also if he is planning to relocate there then he must ask his wife to work as well. A lot of opportunities are available for women employees on husband's visa.
Dubai is a rapidly growing country and hence the living cost are on the rise so is the salary band but the problem is to get a good opportunity in dubai each and every firm asks for UAE experience. As well shifting jobs is not as easy as in India he will have to finish his contract agreement time usually 2 to 3 years as mentioned in the contract.
To sum it up its not a bad option if he is passionate about going abroad as well the standard of living is better than in India.
Regards,
AJ