Where are you staying and for whom is the contract?
If it is for the oil companies, we recieved three meals a day- all laundry and our "chambre" was cleaned daily. If you are at an oil camp, you will spend zero because you cant go anywhere to spend the money. In hassi, you would need to pay for alchol and cell phone cards.
Used sparingly as i didnt drink much I spent USD50 in 3 five week tours.
Otherwise i found most things to be on a par or slightly more expensive than in South Africa.
There i posted something constructive for a change!!!