Is there a specific amount of codes you need?

Title says it all. Is there an exact number of codes you can optimally get each months to get the exlcusive skins? On a bit of a budget, and I’d rather get the minimum cans possible. It means I’ll miss out on some of the double XP, but I don’t mind that.

Buy from Walmart, only get the 5 hour XP codes (best point per minute of do) and I don’t believe there is a limit it’s just one receipt per day tho