A real estate agency wants to send out a biweekly newsletter with the list of...

Because of the complex relationships (multiple objects and property matches), it's best to use Automation Studio to:

Query and flatten the relational data into a single personalized Data Extension.

Then use Journey Builder to send based on that prepared data.

This approach avoids heavy personalization scripting inside emails (which would reduce performance) and makes the sends more efficient.

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Exact Extracts from Salesforce Documentation:

Source: Salesforce Help – Journey Data Preparation Best Practices

→ "For complex relationships and personalization requirements, prepare the data with Automation Studio before injecting into Journey Builder."

Source: Salesforce Help – Personalization in Journey Emails

→ "Avoid heavy personalization logic inside the email. Prepare the personalization using query activities beforehand to ensure send performance."