To save 20000/month you should have a salary of 35-40,000 but since your housing is taken care of savings can be more even if salary is only 30,000. Regarding medical for family, please make sure if they provide medical insurance since the treatment will be provided at government hospitals. Also make sure of the insurance company if they are providing it. QASCO is located at Messaied and is 1 hours drive from hreart of the city, so I guess that your accomodation being provided will be close to the factory. QASCO is a the first steel company in Doha and is a govt organization, no problem to join.