the offer is fair....
it's not a lowball offer,that's the normal rate, specially for contracting companies...
if you applied with a consulting company, you would have gotten a better offer, at least 2K or 3K higher.

if i were you, i'll grab it...
yes, the cost of living here is high, but if you think about it, you have free accomodation and transportation right?...which takes a huge chunk of our salary...

it means you just have to worry about food, clothing and other personal needs...i think 3K riyals is enough...

goodluck....