Any unlicensed or uninsured contractor that gets hurt at your home: you are 100% liable
(Ask to see a license and insurance before the job starts)

Most all work done does need a permit
(Ask to see one before the job starts)

Any contractor using unlicensed and uninsured sub-contractors: you are 100% liable
(Ask to see license and insurance before job starts)

Any people who work on or provide materials for your job and do not get paid: you are 100% liable (Get lien release at each payment)

Any damage done to city or county property: you are 100% liable
(Broken sidewalks, waterlines, pavement)

Any environmental damage done: you are 100% liable
(Dumping trash, draining water, killing protected plants)