I worked in khobar sometime ago and my take is as follows although it might have changed a bit now as khobar is a rapidly expanding city:

1. Villa 2 bedroom compound : 40-60K SAR per annum.
2. work permit : 2-3 months...depending upon on what visa you initially go and how fast is your company's PRO.
3. Hajj: no idea but i saw lot of shops showcasing the hajj package deal.
4. once you get your iqama (work permit), you wife can get the family visa and follow suit in a month or so if i remember correctly.
5. food and other incidental expenses: about half of that in qatar...considering growth maybe 3/4th now.

it is a nice place.bahrain is closeby and once u get iqama you can easily hop across the causeway...so all the best.