No one would bat an eyelid about a driver. However, most people I know have a friendly taxi driver who knows you need school pick up on Sun, Tues, Thurs later than Mon and wed, and fits other jobs around those "permant bookings".
I believe jomidmum is permentaly home educating. You may exclude yourself from the possibility of some schools if you use home Ed as a stop gap for more than a month or two. Tho at aged 5 you may get away with " this is a first school, no previous schooling history".
A shop was on my essentials list when DH was compound hunting. It's more like a corner shop. We use it for mid week milk, bread and icecream, and other top ups, rather than a full shop. I'm sure you could if you wanted to. The other reasonably sized compounds I've visited have similar.
My parents are coming next month
it's been a paperwork head ache but perfectly possible to get close family in.
Cost of living. Food can cost peanuts if you eat like a local. But as soon as you start wanting breakfast cereal, crisps (walkers/lays) biscuits, ie the imported stuff, prices rocket. Petrol is cheeper than water (£10 to fill a tank). Utilities are included in our rent. Eating out, I'd say is similar to UK, but remember no alcohol which keeps it down!
Talk to Jo about hospitals. We have access to the company hospital (!), so haven't experienced local hospitals. The only negatives I've heard is the ease at which drugs are handed out, and maternity care. Most people seem to leave Kingdom to give birth, those that haven't have less than positive stories.
It's very dusty here. I don't think the air quality is too bad. Canadian friends think it's awful. No bad colds in the 6 months we've been here.
Look at getting a relocation allowance, and either shipping / furniture and other stuff you need replacing allowance. ie get them to cover your moving and set up costs. Our house came fully furnished- most seem to be (and not a decision factor, but unusually, we also got TV, ironing board, sheets and towels of furnished).