cover the cost to open the loan (if there is any cost) get the loans and pay it off after a couple payments.

A friend of mine recently saved thousands doing this.

My FIL once bought a car on his credit card to get the points and then paid it off he following month.

Point is, if you're able to buy with cash, just do whichever option benefits you the most. But be cognizant of fees from whichever method you choose.