Do I need much money for the stay in San Francisco?

There are not many places in town to spend money. The stores sell food (non-perishables, fruit and vegetables, bread), soft drinks, toiletries, etc. at prices a little higher than in Quito. There are NO banks or ATMs in San Francisco or in Muisne (the closest city) therefore it is necessary to calculate beforehand how much money one might need until making a trip to a larger city. It is necessary to have lower denominations bills in San Francisco (USD 1, 5, or 10; no larger).