Thank you all, very useful stuff.
citygirl - re school fees, do you mean 6000pesos per month per child? or dollars? (this may seem like a silly question, but I'm discovering that the cost of international schools varies greatly from country to country and bears very little relation to salary rates, cost of living etc)
mmoon- it's not that we need our expenditure to be predictable, it's just that when my husband starts looking at jobs in BA we need to have an idea of whether the salary will support the kind of lifestyle we want to live. Really all we need is a snapshot of what it's like right now and I think ElQueso's comments will help in this regard.
Regarding locations, we're really dependent upon where (and whether) my husband can find a job. I don't consider myself to have 'asthma issues', it's just that the air in India is the worst in the world. I've consulted the UN figures on this and the annual mean pm2.5 for Kolkata is 50, where BA is only 16, so significantly better. I appreciate that BA is a rapidly changing place and that there are no pollution controls, but for the moment it is a huge improvement. And seeing as I've never had 'asthma issues' before, despite having lived in Bristol England for many years which factors in at 15, I think I should be able to manage in BA! Let's hope so because if the whole expat thing doesn't work out then I have to go back home to Bristol! Thanks for the suggestions anyway, if I do continue to have problems in cities then obviously I'll have to move to the countryside and will happily do so but in the meantime I'd like to try some 'cleaner' cities like BA to see if we can find one that works out.
So, ElQueso, if I understand correctly...we would need to arrive with a stack of cash, then as we have no contacts in BA we would more than likely have to take a 6 month contract, which we may be able to get extended by 6 months. At that stage we would have to find somewhere new to live (on another 6 month contract) unless we had befriended a local who trusted us enough to put up their property as a guarantee. Sounds unlikely, so most likely we would have to move every year then? If this is the case it's seriously putting me off BA. Before having kids I moved around a lot, often every year, it's easy as a single person, but with a family it's a pain in the neck and I'm really looking for somewhere we can just settle in for a few years.
The rental situation can be very complex, or very simple. The thing with the 6 months first contract and the second being the limit by law doesn't mean that you can't find someone who will even rent to you without a guarantee, for as long as you want to live there, under consecutive 6 month contracts, for years. i was giving you the sort of legal end of things, but there are owners who are either unaware that a 6 month temporary contract, extended for a third time, actually gives the renter a default contractual situation of a two year long term lease. There are others who know and don't care, who rent anyway on extended temporary contracts.
Personally, I too despise moving. I'd stay in a bad situation, if I could find one that was survivable, just to keep from moving!
To use me as an example of how things may play out: for my first year, year and a half, here I lived in temporary apartments. The longest time I was in one was 2 months, but in 2006-2007, the tourist market was going full guns and it was simply hard to find any apartment that was not booked, at least for a few weeks here and there, which would break up any kind of continuous short-term lease. Now, the tourist situation isn't as good as it was, but it seems to be improving - my wife helps manage temporary rentals for a guy we know and for the last two years it hasn't been all that busy, but in the last few months things have picked up significantly. That may mean a return to difficult times finding a temporary lease for longer than a month or two, or maybe not - just don't know yet.
After that first year, year and a half, I got lucky. I had a friend who I'd met here, an accountant from the States, who had paid all of his two year lease in advance in lieu of having a property guarantee. About 10 months into his lease, he was recalled back to the States (he was telecommuting for a company, but got promoted and the new position required him to be present in the office) and he had already sunk a lot of money into his future here. I was newly married and he knew I was looking for an apartment, so I moved into his apartment (actually bought all of his furnishings - and that's something to think about: rarely do long-term leases include furniture. Temporaries almost always do include furnishings) and I got a little over a year in his place. That was the first time I'd been able to stay for more than a couple of months! I actually bought a desk to work at instead of the kitchen table!
In the meantime, I was employing people here and one of my programmers and I had developed a pretty good friendship. He had an apartment in Cordoba and he offered it to me as a guarantee for us to rent a house in the far suburbs (about 40 kilometers outside the city), in a closed neighborhood (good, clean air there, I must say). We stayed there for two years, but I had job problems and things got too expensive out there so we moved into the city. Know that most owners want a guarantee on property that is in the city, but you can find people who will accept something even as far as Cordoba, as I found out.
My second long term rental - I had also made friends with another expat who owned an apartment in town. He offered me a guarantee, but I had to give him a deposit to ensure that I wouldn't screw him over by screwing the owners over (because he, as guarantor, would be responsible directly). I lived in that apartment for 4 years (nearly heaven!) and ended up having to leave because the owner got greedy and decided he could rent his apartment out for nearly double what I was paying. As far as I can tell, he still has not rented that apartment out, after about 18 months.
So the apartment I'm in now, I got the guarantee from the father of a friend of my wife's. His apartment for the guarantee is in Mar del Plata, another non-CABA (Ciudad Autonoma de Buenos Aires) apartment. I paid him straight up the value one month's rent for the guarantee (and rented through Remax, which cost me a month and a half rent for their commission! They let me pay it over two months...). That was about 18 months ago. Moving here can be expensive when you talk about long term leases, paying the movers (though certainly a much better value than moving in the States, by far), the deposit on the new apartment (I and almost everyone I know have had bad luck getting the deposit back from owners after having ended a lease) and often paying someone for their guarantee. We told the owners that we wanted to live here for a long time because we were sick of moving and they were delighted to hear that. And then about 6 months ago, we got news that their ownership of the apartment was contested by their father and they are forced by the court to sell their apartment (long story) They can't kick us out until our lease is up in the middle of March (and really, it would take at least a couple of years to kick us out if we refused to leave, but it would affect the people we got the guarantee from and there is no way I'd do that, contrary to any advice our forum-resident Argentine lawyer gave me to do just that!).
I've had terrible luck with landlords renting here. I mean, really terrible. I have occupied somewhere around 13 different apartments (most in the first year and a half) and one house in the 9 years I've lived here. I've yet to get my deposit back on a long term rental and we take care fo the places we live in.
However, I have a friend who has spectacular luck, at least at finding places without a guarantee (although he just got screwed on getting his deposit back). He's never needed a guarantee. He just left a small apartment right across from Recoleta Shopping that he occupied for 9 years. He had previously made a contact with the owner of an apartment that is incredible (about two blocks away from the congress building on Av. de Mayo, a tower with a dome and three floors, on the roof of a big apartment building) - the owner is American and is happy to lease to my friend for the foreseeable future without a guarantee.
My biggest problem may be similar to yours, depending on how big a space you need for the kids. My wife and I have three teenage girls (well, one is almost 20) who are her sisters and came to live with us, from Paraguay, to get a better education than what they got back in the poor part of Paraguay where they're from. I work at home, so I need an office. Big apartments at a good value in a nice neighborhood are hard to find in the city. You may have much more luck outside the city (some bad places, some good places) or in another town or province (like Cordoba city in Cordoba province, or Mendoza in the north, etc).
It also depends on how much money you have to spend, how small a space you are willing to rent, how far to travel for work, what kind of work you can get, etc, as to where and how you can live, and often the contacts you can make. You may not have any choice, should you all decide to come, but to live in temporary apartments for the first year or so until you make enough contacts to start finding ways to get longer term rentals. But that also gives you all time to figure out what to do with the kids (schools, good place to raise them, etc) and find work, and so on.
I don't want to put you off, but you need to know about these things to make a good decision and at least make the choice to come with your eyes wide open. I've told my wife many times that I would prefer to live in Paraguay, in Asuncion or Encarnacion, but she lived most of her life very poor in Paraguay and has a lot of bad memories and can't be convinced - yet. But we could live there for about 1/2 to 1/3 the cost of living here (including decent schools in Asuncion at least, probably in Encarnacion as well, though I haven't visited there yet, just heard good things about it), at the same level of lifestyle (at this point in time, better access to electronics, furniture and other items) - but I'm also not a partier, which many people who are here see as a good thing about Buenos Aires, at least).