Hello @MarketerL52338 ,
Assuming you have permission to email these contacts, and the estate agent has allowed you to utilize their list, the quickest and easiest method would be to upload it via file. You'd want to get a CSV file of the contacts, make sure it's properly formatted for upload, and then go through the import process.
You'll also likely want to speak with our Review team, to make sure this list and your utilization of it are within our Compliance guidelines and permission policy.
Contact import methods
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