Just goes to show how everything is uncertain here.
4 years ago, I bought a car with cash. I tried to get a CUIL from ANSES with my passport and they absolutely denied me this. The only thing I could get as a foreigner, according to them, was a CDI.
I went to every bank I could think of, around that time (not associated with the car purchase), to try to open a savings account and was denied every time. About three years ago, when I applied for my residency, it was required that I get a bank account and my lawyer took me to Banco Galicia where he knew someone that opened a bank account for me. Having the precaria at that point, it would probably have been possible for me to do it at that time myself.
I've heard many anecdotes about people being able to open bank accounts without a DNI, but I was never able to do so, nor do I know anyone who did - with one exception.
I have a (very) rich friend who spends half his time here and half in the States. He was able to get some kind of account set up for transfers through CitiBank, in conjunction with his accounts in the States. But he has more money than God and people with that kind of money can always find ways to deal with inconveniences.
I don't know, I've always been extremely unlucky on things like this it seems. I had heard other people able to do it and it never worked out for me.