General Liability provides coverage if you are liable for damages to other individuals arising from your premises, general operations (ongoing and after completion) and products manufactured or sold.
An audit may require you to show proof that sub-contractors had their own insurance coverage. The sub-contractors' certificates of insurance will prevent you from being charged for their exposure.
At the end of the policy term, the insurance company will review the policy and either charge or credit the policyholder based upon an audit of estimated figures. Examples of estimated auditable items include sales and payroll. Audits can be performed onsite by an auditor or via mail or telephone. A premium is charged for audit estimations.
This damage will be covered only if that type of coverage is purchased.
Most personal auto insurance policies will exclude business use of your personal auto. So the answer is you most likely will need a seperate business auto policy if you are using your auto for business. There are a few exceptions to this. Some personal auto insurance policies do have a business use class that was intended for the accountant, lawyer, counsultant type who drives from client to client all day long. Or possibly even a real estate agent might find coverage on the personal auto policy. Each insurance company has different rules on what types of "business use" they will tolerate.