Welcome on board eqeman 
I am publishing some figures about the cost of living in Amman so that you can an approximate idea.
Restaurants Â
Meal, Inexpensive Restaurant   7.67 $ Â
Meal for 2, Mid-range Restaurant   27.91 $ Â
Combo Meal at McDonalds or Similar   7.21 $ Â
Domestic Beer (0.5 liter draught)Â Â Â 4.02 $Â Â
Imported Beer (0.33 liter bottle)Â Â Â 6.03 $Â Â
Coke/Pepsi (0.33 liter bottle)Â Â Â 0.57 $Â Â
Water (0.33 liter bottle)Â Â Â 1.01 $Â Â
Markets Â
Milk (regular), 1 liter   1.73 $ Â
Loaf of Fresh Bread   1.92 $ Â
Eggs (12)Â Â Â 1.42 $Â Â
Fresh Cheese (1kg)Â Â Â 15.65 $Â Â
Chicken Breasts (Boneless, Skinless), (1kg)Â Â Â 2.64 $Â Â
Water (1.5 liter bottle)Â Â Â 0.76 $Â Â
Bottle of Wine (Mid-Range)Â Â Â 29.11 $Â Â
Domestic Beer (0.5 liter bottle)Â Â Â 1.98 $Â Â
Imported Beer (0.33 liter bottle)Â Â Â 5.78 $Â Â
Pack of Cigarettes (Marlboro)Â Â Â 2.88 $Â Â
Transportation Â
One-way Ticket (local transport)Â Â Â 0.59 $Â Â
Monthly Pass   18.84 $ Â
Taxi (5km within center)Â Â Â 2.40 $Â Â
Gasoline (1 liter)Â Â Â 0.79 $Â Â
Utilities (Monthly) Â Â
Basic (Electricity, Gas, Water, Garbage)Â Â Â 70.10 $Â Â
1 min. of Prepaid Mobile Tariff (no discounts or plans)Â Â Â 0.19 $Â Â
Internet (2 Mbps ADSL flat)Â Â Â 61.13 $Â Â
Sports And Leisure Â
Fitness Club, Monthly Fee for 1 Adult   65.98 $ Â
Tennis Court Rent (1 Hour on Weekend)Â Â Â 6.60 $Â Â
Cinema, International Release, 1 Seat   7.92 $ Â
Hope this might help you meanwhile to calculate your cost of livings based on your income.
Regards
Source: Cost of Living, Numbeo
Figure updated on December 2010