The easy refund cases are plain game purchases, but pre-orders and add-on content follow different rules — and that is where requests get denied. A pre-order is usually refundable any time before release; once the game launches, the standard purchase window (like Steam's 14 days / 2 hours) takes over. The Steam policy page spells out the pre-order switch and the DLC exceptions.
DLC and in-game items are the tightest category. On Steam, DLC is refundable within 14 days only if the base game has under 2 hours played since the DLC purchase and the DLC itself isn't consumed, modified, or transferred; Valve in-game purchases are refundable within 48 hours if not consumed. Other stores treat most in-game currency and consumed items as final sale. Check the specific platform page before assuming anything is returnable.
The trap is mixing categories in one request — a denied DLC refund can make it look like "nothing is refundable" when the base game still qualifies. Separate the items: verify the base purchase with the eligibility checker, then handle each add-on under its own rule. Consumed or transferred items are almost never refundable anywhere, so don't waste a request on those.
Bottom line: pre-orders are flexible until launch, base games follow the standard window, and DLC/in-game content is the exception-heavy category. Read the relevant platform page before you buy add-ons so you know what you can later return.