It would be good to check with the people you work with, if they can help you out during your first few weeks in Qatar.

Per my understanding, to rent a car, you need a credit card. and if you are a resident of Qatar, you will need a valid RP. or they may keep your passport as insurance.

The people you work with (if you are single) may help with transport to the office and outings.

Just my thoughts, I could be wrong.