Checkout flow for buying as guest

I’m working on an e-commerce web site and was reading more about the checkout process. I’ve found this answer, talking about the benefits of not asking users to create an account on the web site in order to buy something. Instead, the advice is to let them buy and, later on, try to interact with that user, trying to create an account. This point is very clear to me, but I’m still in doubt on how to best design the initial step, where I need to, first, identify if the user is a new user or if he already has an account.

In my case, the user has 2 options to create a new account: E-mail/password or Facebook login.

When the user clicks on the button to initate the checkout process, I have these options:

  1. Identify: Check if user has an account or if it’s first time buying;
  2. Address: Fill in an address or use one (if avaliable);
  3. Payment: Credit card payments;
  4. Confirm: Screen to show a confirm message (Congrats, your purchase was successful);

The “Identify” step is where I’m in doubt. For example, what would be a good design to ask for the users login credentials or just identify his name/e-mail(?) to get in touch later on?

Option 1

For this, I’m working with this initial mock design:

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My concerns with this design would be:

  • I feel like I’m already showing a lot of information all at once;
  • If the user is a new user and just fill his initial data (email and name) do I need to validate his e-mail? For example, a “confirm e-mail” field in order to avoid typos?
  • What if the user doesn’t mind creating a new account?

Option 2

Another option would be to have a button “New user” or “Create an account” and then, based on the option the user selects, the view would change (hide/show the proper form based on his choice).

enter image description here

I feel like the second option is better, the design is a bit cleaner, but it also feels like it adds a next step (e.g. step 1.1) during the checkout process.

Option 3

The third option would be to treat the “New user” and “Create account” as one single case, I mean, do not show the “Create account” option here, just guide throught the “New user” process, and on the confirmation screen asks if the user wants to provide a password to access his information in the future.

Any other advice or cosideration are welcome. Thanks!