Can anyone give me a rough estimate of the price per gallon of gas in South America? Just an average will do. Also, what would an average meal cost? Not sure where I will be travelling yet but want to have an idea to know how long I will be able to afford staying there.
Thanks for any input!

I would invest in a continent-wide guidebook to answer some of those questions. Fodor's has one for South America, and individual country books for Peru, Brazil, Chile and Argentina.

Gas prices vary widely from country to country. Venezuela is dirt cheap that way. Ecuador is pretty reasonable. Both are oil-producing countries. Gas is about the same price or more expensive than the U.S. everywhere else.

We took a year out in 2008 to travel the world and spent 5 months in South America. our average budget for the trip was $100 perday (for two of us) but this dropped (I would guess) to around $60-70 p.d. in SA. We stayed mostly in hostels using www.hostelworld.com or www.hihostel.com usually in ensuite double rooms and usually ate in local restaurants. we certainly did not stint on anything and it would certainly be possible to spend a lot less.

Prices for meals will vary from country to country but even more by the type of restaurant. In Peru we could eat great ceviche in a local market or restaurant for circa $2 or a great (and I do mean great!) steak in Buenos Aires for $10pp or less. If you really want to keep costs down, buy food in local markets and cook in the hostal kitchen. When reading guide books for prices beware inflation in most SA countries. e.g. we found prices in Argentina to be much more expensive than we had been led to believe by the guide books due to the delay between writing and publishing (The LP website may have more up to date info). But even so, prices were a lot cheaper than here in the UK (but then, virtually everywhere is!)

We were travelling during the oil crisis so my views on gas prices are somewhat irrelevant but we did hire cars in Argentina and it did not seem particularly expensive or cheap.

Of the countries we visited Chile was the most expensive, followed by Argentina and Peru was certainly the cheapest.

As average income vary 4 to 5 times among countries so do prices. In general prices will be higher in Chile and Argentina and in pounds and dollars have been increasing as both pesos have increased in value. In Chile gas costs about US$5.00 a gallon, in Venezuela about 50 cents so you cannot generalise on prices.

In Argentina living costs completely depend on the city and the district... the dollar is worth AR$3.8 at the moment. Buenos Aires is more expensive than the provinces or smaller towns, a meal in Buenos Aires is around AR$20 for pizza and steak and then goes up if you want sushi, in a nice district you can pay around $20 - $30 for a cocktail, and $12 - $20 for a drink, but BA is very versatile so if you're on a budget you can stick to empanadas (filled pasties), bakeries and choripan (Argentine hotdogs!).

Petrol costs AR$3 a litre and so is very cheap!

Hope that helps!

Gasoline in Venezuela is virtually free. It cost about $2 to drive a big SUV more than half way across the country last year. Renting the vehicle was not cheap. I found gas in Chile to be more expensive than in Canada when we were there in 2007.

As has been said food prices are all over the map depending on where you are and how you wish to dine. If you can afford to rent a car you will be able to afford to eat reasonably well.