Question: Some mates and I have the amount to cover the cost of an item but have a credit limit lower then the price. The purchase has a hard requirement that the payment method is a credit card. So, my mates and I put a negative balance on the card (I.E: The balance is 0 and then we pay something like 16,000 on it, making the balance -16,000 so we can make the large purchase putting the -16,000 balance back to 0).

Could we make the purchase using this method?

Answer: 
Typically, that does **not** work. Calling the bank might give you different info, but there is a risk that it won't work, even though the bank explicitly confirms it (happened to me, BoA). At the end, the original credit limit of the card applies, even if you overpay it with a million.

You can try to call and ask for a limit increase, even only temporarily; the risk with that is that your credit score might probably go down, and it might get declined, so you end up worse than before.

Also, once you transfer the money onto the credit card, it takes a lot longer to get it back. The official claim is typically '4-6 weeks', but it might work in 10 days if you are lucky.

My solution was to take out cash and hand it to a (personally and well-known!) friend, who had enough limit on her credit card and made the booking for me. The bank impressed only by being extraordinary disinformed, self-contradicting, helpless, and counterproductive.
It seems that it depends by bank.

In Argentina, I can overpay or "charge" my credit card. 

If you go to Visa Home page, there is an option "Balance status" (or so).

There you can see `Available to make purchases`: XXX, `Available to make purchases in installments`: YYY

When I tried this, the only amount that increased was the first one, i.e the amount that you can use to make a payment in one payment only (no installments).