We had a roof inspected for a real estate purchase. It’s a four year old Malarkey Legacy, Class 4. Three large areas are covered in blisters. The roofer who installed it says that they come and go. I‘ve never heard that. Second opinion roofer says it needs to be addressed as it is a manufacturing defect. Roof has good ventilation. Has anyone had experience with this and what was your outcome? Thanks in advance.