The option to rent or buy a game is only available during the trial.
Overlays, like the one below, will appear in-game. These provide the option to buy the game, and where available, to rent as well.
You can do this by clicking the green 'Buy Options' button.
You will then be able to select whether you'd like to rent or buy the game, or click 'Back' to continue playing your trial.
Once you've made your decision, click the green 'Add to basket' button. This will then take you through to our payment portal where various options are available.
If you rent the game, you can play on instantly. If you buy the game, you can also play on instantly and you'll be sent a Steam key by email. You can continue to play our version of the game for 2 days while you transfer your progress to Steam.