Thank you for the responses!
Zikreet, the tax equalisation is because DH will be classed as an international consultant who may be asked to work in a number of countries (Australia and Canada have been mentioned!), although his initial assignment will be in Qatar. He will be paid in Scotland in £, with a proportion paid directly to a Qatari bank in line with Qatari law. But it will be calculated at the exchange rate on each payday. Hmm. I hadn't considered fluctuations in the exchange rate!
The school fees - they will pay for DD to start this year (policy covers kids from 4-18) and will pay up to 50,000QAR for the year, which includes registration fees and deposits but not books or uniforms. If we're still there when DS turns 4 then he will get the same.
Car allowance - 3500QAR a month for a leased vehicle. I know I will need a car as well but we haven't really planned that out. How much do secondhand cars go for, if it was to be bought outright? I know there's lots of advice re getting big SUVs, but I'll never in a million years manage to parallel park an SUV! Do I really need one - won't a smaller car do? I did think that to start with I could just drive DH to work and then take his car for the day, which is what we did when I was on maternity leave here. I don't want a three year car loan as the contract is for 1 year initially, although may well be extended - we should know that by March at latest.
The basic salary is £32k, supplemented with a COLA and disturbance payment which takes it up to £40k. Then there's a bonus of about £6000 for completing the year's assignment. It's public sector - he will be working for the international arm of a Scottish public sector organisation which is sub-contracted to the Qatari public authority. I think hence the slightly weird pay package, because yes, that's how it seemed to us - very generous housing and car and schooling allowances, but the basic salary was a bit low in comparison!
Thanks for the info re food bills - I was budgeting about £200/QAR1000 per week for a rough estimate, so that seems about right. I will try to buy as much local food as possible. DH hardly drinks at all and I drink mainly on social occasions. Can you buy drink in duty-free on your way in, or is that illegal?
I will get DH to ask about the multiple-exit visa!
Can I ask about mobile phones - did you keep your UK phone contract or take out a new one?
I think we're going to do it. At the moment on two salaries we're penny-pinching and not saving. If we can have the same quality of daily life (bearing in mind that the housing will probably be nicer than our current mouse-infested rented house, and that DD will benefit from private schooling) but without me working, and with DH's bonus coming at the end of the year to save, then I think it's worth it for the career boost to DH. I am not too worried about my career initially - if they ask DH to sign a contract for a further 3 to 5 years then I will look for a job out there too. If we come back within 2 years my job here will be kept for me.
Sorry this is such an essay!