So what's a reasonable amount to budget

I know "reasonable" is a loaded term but I'm wondering what the ballpark estimate is of what people spend a month living well but not extravagently. Living well = a lifestyle of an average middleclass person..Can you live fairly well on $1000 US dollars a month? Do you need $1500? Less, more? My thought is that I'll move down there for 6 months or so sometime in the next year. If I like it, I'll probably stay & buy a place. If I don't, it will be a heck of a vacation & I may buy a place anyway as an investment.
I realize that finding a job down there isn't feasible so I want to make sure I have enough in savings to not worry about money. I'll probably be working on starting up a business but realistically that won't be income producing for at least 6 months.
You'll need to rent a place, which could be anywhere from USD 350 to USD 600: let's say USD 500 (these are exorbitant figures for the locals; you're paying short-term USD rates applicable to tourists). Other than that, USD 500 a month (i.e. 1500 pesos) should suffice for a comfortable but not extravagant lifestyle: you can eat out all the time, travel a bit, entertain a bit. So USD 1000 is a good figure. Bear in mind that this is a good executive salary in Buenos Aires.
With regard to buying a place as an investment, make sure you get expert counsel. Apartments only get to be rented sporadically. There are rules and regulations governing the conduct and tax liabilities of a non-resident foreigner who buys property in Argentina. The market is not as liquid as a realtor might suggest: you may have problems if and when you decide to sell. And Argentina is volatile. Forewarned is forearmed.
350 - 600US is not exorbitant, this is what it costs to live in Recoleta, Belgrano, PV, or Barrio Norte whether you are a local or not, and these are of course the areas most foreigners desire to live in, unless you go to Zona Norte which I think are probably approx the same costs (someone who lives out there can verify?) .
350 is pretty unheard of in these areas unless you can get yourself a local to sign as your guarantor AND are willing to commit to a minimum 1 year and usually 2 year lease. The only places I have seen that price are places with no fans or A/C. Local friends of mine are currently looking for an apt in Palermo and they are looking at the same prices as a foreigner. However, when you start paying $750 and up for a place, then you've pretty much crossed the threshold into upper class and tourist only places.
I don't know what town your from but this may give a good comparison to clarify how things work here:
I'm from Vancouver. There I paid $650 CAD (500US) a month and lived in a 900 sq ft modern apt with ensuite laundry, gas fireplace, balconies, two parking spaces, AND a roomate (lol). On top of that I paid $45 CAD (say about $37US) for my high speed (and true high speed) internet, plus my gas/water/heating plus plus plus etc, so say it avg'd about C$775 per mo.
Here I pay 500US but 1) I live on my own in a 35 sq m place (apts are smaller than NA of course) 2) I have maid service once a week 3) I have cable & "high speed" internet included in the price. I still have a balcony, I have no ensuite laundry (not many places do here, you take it out), no parking spot (I don't have a car), no fireplace etc.
Also, if buying a place here as a foreigner, I believe it's big bag of cash on the table, not 100% sure but someone else can advise I'm sure.
Rents in BA can only be considered cheap based on the city you're coming from. Sure, this town is cheaper than home but it's certainly not run around naked shaking your fistful of dollars in celebration cheap, lol!
Well, coming from NYC, rents in BA are in fact run around naked in celebration cheap:) - but I promise not to do that.

Wolf, I agree with the concerns with the buying but I think it's a great investment. And going by (whom I rented my apt through when I was just there), it seems their apts have a good rental rate. No, nothing is certain but I think it's a good gamble...

Syn, after doing research, it appears mortgages are not exactly an option so it is in fact "bag of cash" transaction if you buy an apt. Hence why I want to be very, very sure.

I loved BsAs but definitely want to spend a larger chunk of time there before I commit fully. Also need to make sure my business model is valid as well;)
There are some small studios still going for USD 350 (or were until a couple of months ago). Try Reynolds for starters; there are some other rental agencies as well.
Compared to New York rents -- which can run into thousands, even tens of thousands a month -- BsAs is of course ridiculously inexpensive.
If you agree with the concerns about buying, why do you still assert unequivocally that it's a great investment? Go to a site like Reynolds, which has a rental schedule for each of their listed properties, and observe the gaps in rentals for many of the properties. Also read their prognosis for property prices. Unlike most other realtors, their words are measured and cautious.
For a New Yorker the odd USD 100,000-200,000 may be chump change, but why endanger it? When you visit BsAs, try to look beneath the surface, where all sorts of problems are simmering (inflation, labor disputes, crumbling infrastructure), and which happen to be rooted in Argentinian history. The country has had a chequered fate for the last sixty years, and there's no good reason to believe that that era of tumult and crisis is in the past.
BsAs is a lovely city to visit time and time again, but be wary of rushing in where angels fear to tread.
I think it's a great investment for several reasons
1) US Housing Costs. Not sure if you're aware of the housing market here but it's out of control. Yes, I think we're seeing the end of the bubble but still, 100K in NY won't buy you anything - literally. 300 square foot studios are selling in the $300,000 range. So to buy an apt in a nice section of town for 100K is the opportunity of a lifetime.
2) Rise in tourism. No, there is no crystal ball but I am hearing a lot of people talk about how they want to go to BsAs. I was at a cocktail party last weekend & I would say about half the people there either were planning on going or knew someone who had gone. With the fall of the dollar against the Euro, South America is looking better & better for a lot of vactioners. I think that buying a rental property may prove to be a smart move and I think that renting will probably cover the maintenance costs at least (anything above that is icing on the cake).
3) Exchange Rate. With the fall of the dollar against the Euro, vacations and/or buying in Europe is simply out of many people's reach right now. Buenos Aires is one of the few major cities where a middle class American can come & spend without worrying about money. I think as long as the city stays safe, a lot of people are going to start taking advantage of the buying power of the dollar...
I know there are problems in Argentina. But I think with problems come opportunity.