This is the entity that the carrier will write a check to, or defend in court if you have a claim. Do not put a DBA here. If you are a sole proprietor put your name.
If you do not have a DBA just enter N/A
Some carriers rate based on the area occupied by the business.
If everything in your shop burned up, and you were buying replacement equipment, inventory, and so on brand new - how much money would you need to replace everything?
Some carriers rate general liability off of payroll, and most use payroll to rate coverages like EPLI, Employee Benefits, Ohio Stop Gap/Employers Liability.
Most carriers use annual revenue as the rating basis for general liability.