I am currently in the GCC (middle east) and am slightly in a rut. i
have a choice of 3 cars to choose from and dunno which one i shud
pick. Camry, Maxima or the altima. the criteria is mileage,
maintainance cost in the long run...say 5-7 years and after sale value
+ value for money.

Compare mileage etc here:

http://autos.msn.com/research/compare/default.aspx?c=0&n=3&i=0&tb=0&ph1=t0&ph2=t0&dt=0&v=t101780&v=t101820&v=t101170&v=t100746&v=t100872&v=t100743&v=t101763&v=t102510&v=t101694&v=t101377&v=t101780&v=t100850&v=t102142&v=t101743

You havent said which engines your are considering so it is tought to
give you the proper direction...the above link will let you alter the
engine.