I have customer and leads form. They have same shared attributes like Name, Phone, Address and Leads have it's specific attributes like First Contact Time, Contact Via. I want to separate Customer and Leads into different form but my boss want to add Customer into Leads form as a subform they have same attribute so no need to have Customer form.

My question are:
1. What's the pros and cons of each?
2. For the second option (Customer inside Leads form as a subform), how to design the form?