how much???salary of sr biomedical engineer?

i have recently joined this group.
I am planning to shift to qatar from india soon.
i need your support to decide whether the job offer given to me is good or not?

i am having 7 years of experience as service engineer in hi end medical equipments in india at various MNCs.

I am offered 8k basic and 4k of other allowance.
The company says that they will give permanent visa for my family( wife and 1 year old kid ) after 6 months of my probation period is over. when this happens i will get the other allowance i.e. 4k. till that happens i get 8k only for 6 months.

I need to know whether this is a good offer and should i accept it or not.

please tell me what is the expence out there like food, lodging, travel etc.

i hope you will answer me soon and will give me suggestions on this.