Food is more expensive if you buy all imported stuff, especially around Christmas. One bag of Walkers crisps is about 4qr, Waitrose dried pasta 9qr. M and S is about the same as UK but they only stock expensive things and no frsh food sadly.
Electric things are aabout the same, not quite such a good range.
I think you have to have a residents permit to get an aramex account, then you go in, pay a deposit and register. The UK address is in Slough, it usually takes 2-5 days to reach here then they text you to come and collect it. It's fantastic as long as you tell your family not to send you heavy presents, you pay by the kg to collect it.
Ask as many questions as you like, it's very important!!