As I've said in other posts on this forum, there's no point trying to sugar coat the pill, Luanda is known as the most expensive city in the world for ex-pats for a very good reason.... it is!!
Domestic shopping for a family of 3 will easily cost you $150 a week, if you like your luxury items then you can double that. (as an idea, we made pizza yesterday, mozzarella cheese $10 for 25g) tomatoes will cost about $2ea or so, a litre of UHT milk about $4
If you have a youngish family then Luanda Sul really is your best option - it's far cleaner, safer and more friendly than the city itself.
Transit time to the city can be an issue (2hrs each way isn't uncommon, but more roads are being built which should ease that.
There are 2 international schools in Luanda, one in the city and one in Luanda Sul.
As I understand it, both have waiting lists for all years, so admittance is not automatic -
I have a friend here with a 6yr old girl who they have been unable to get into a school for nearly a year now.
Contact the school first to make sure.
The school is very expensive, I've heard about $30k a year, but I'm not certain.
There is a decent, western style shopping centre in Luanda Sul that has a number of eateries and an 8 screen cinema showing all the new releases in English. It's not expensive and makes a nice evening out.
Other than that, if you live in Sul then there will be things going on on your compound etc etc, there are also a number of ex-pat get-togethers in the city that can be attended.
Apartment availability is good right now, I know of 2 very nice 2 bed apartments on a secure compound in Sul for rent at $10 - $12k a month
There are also any number of new build places available if your budget will stretch a little higher ($10k a month is the lower end of the market for sure)
The only rental agency that I know of with a website is www.casa.sapo.ao
No further updates on safety and security, the situation here is pretty stable right now, petty crime is really the only thing to worry about.
If you're considering coming here, make sure that you have thrashed out all aspects of the package before arriving.
You really don't want to have to drive yourself here.
Make sure evacuation medical insurance is included.
Housing costs are massive - make sure your employer gives you a sensible budget.
On a compound, security will be included, if you're in a house in town make sure you have security provided.
Water and power are often off for long periods, make sure you have a reliable generator and water storage.
If you can get the employer to agree to a certain number of flights home per year then do so, there's very little in the way of "amenity shopping" here, most wealthy Angolans travel to Portugal, Brazil or SA to shop.
Lastly, learn some Portuguese, many people here speak a little English, but your life will be so much easier if you can speak Portuguese.
Hope this helps, I've been here 2 years now and still love the place!