you said you have a good job in europe.  if its just 2x (do not include the other benefits) then, the offer is not good.  and since it is a managerial position, the offer is low.  one thing more, you are in UK, the offer should be higher because nationality matters.  dont think of the accomodation or transpo..etc..etc.. think of your basic salary.  all offers for accomodation and transport are given to almost all who works here in qatar.