Need an independent email module.
Similar to this: [login to view URL]
But more advanced.
Each user (staff member) should have its own email as well as default one.
The whole conversation should happen within Perfex.
Each email could be created to Lead, Customer, etc. Just like Perfex offers.
Once we create a customer from a lead, the whole customers conversation would need to be attached at hes customers profile.
Where the whole history of the conversation would be visible with that customer.