NANNY TAX: If you hire a nanny, housekeeper, gardener or other household employees, you could be responsible for paying those workers' federal and state payroll taxes, just like any other business owner.

THE THRESHOLD: A key factor is whether you pay each of your employees $1,800 or more a year in wages. If you do, you're on the hook for their payroll taxes.

KEY DISTINCTION: You're not responsible for payroll taxes if you hire independent contractors, only household employees. They typically work in and around a home, at the direction and control of the person who lives there.