One of the best ways to save on a game is by purchasing discounted pre-paid Microsoft Store credit, essentially rewarding buyers for locking their cash down ahead of time. Amazon, Newegg, and CDKeys are all retailers known for discounting pre-paid Microsoft Store codes in the past, often cutting $5 to $10 at a time.
5 easy ways to save money on digital Xbox One games | Windows Central
www.windowscentral.com > 5-ways-save-money-digital-xbox-one-games
Open the Xbox mobile app, then sign in (make sure you're signed in with the Microsoft account you want to redeem the code with). Press the Menu button in the upper left corner. Select Microsoft Store from this list, then choose Redeem a code. Enter the 25-character code, then follow the prompts.
How to redeem gift cards and codes | Xbox Support
support.xbox.com > help > redeem-codes-gifting > redeem-prepaid-codes
Delivery is FREE with an estimated delivery timeframe of 1-5 business days, however may take up to 6 days for outlying areas.
Shipping options, costs, and delivery times - Microsoft Support
support.microsoft.com > en-us > account-billing