@KazoomKids 

My recommendation would be to send one email but use dynamic content to show/hide the content based on what the customer purchased. This can be dynamic based on specific products or collections they purchased from. It will be based on the purchase event and the data that comes into Klaviyo. 

For example: 

• You create a section for each product that only show if they buy the conditional product
• If someone buys product A but not product B, they only see the section for product A
• If someone buys product A & B, they’ll see both sections

You can learn more about how to do this here: 

https://help.klaviyo.com/hc/en-us/articles/115005258208-Show-or-Hide-Template-Blocks-Based-on-Dynamic-Variables

The one thing you’ll want to keep your eye on is the size of the email. I haven’t tested this myself but others have mentioned that dynamic content, even when hidden to the subscriber will still count toward the total size of your email and could cause your email to get clipped in gmail. If it’s 5 products you’re likely fine depending on the content you include. If it’s 100, that could be an issue. 

Hope that helps!

This article explains how to share this type of asset: https://help.klaviyo.com/hc/en-us/articles/115005256968-How-to-embed-assets-directly-in-an-email-#you-will-learn0

Generally you can’t send a PDF attachment through Klaviyo directly and doing it outside of Klaviyo to a large audience would likely end up with all of the emails going to the spam folder. 

Even a link to a document can be seen as potentially risky. It’s probably better to get the content onto a webpage or have a PDF viewer on your site where people can land and see it that way.