Make sure your salary is not any less than 20000 QR ($6000).
Rent here is outrageous, if it is not provided in your contract the least they can do is to provide temp. stay for at least 3 mo.
Contact any friends or friends of friends, it's good to know someone in a foreign country. Watch youtube videos about Qatar. Traffic here is crazy. Construction is everywhere. Being away from family and friends is very hard. Good Luck!!