I'd like to have customer details kept hidden from my sales agents.
For example, a lead is created for customer@123corp.com. My sales agent should be able to reply within the Odoo app but he should not be able to see the customer's email.
Is it possible to do this in Odoo or would this require a custom module?
Have a look at access rights (Settings > Groups for example) I'm sure you can set these kind of restrictions with rights I just don't know the exact solution so I'll leave that to somebody else :)