W9 or Tax ID # on Airbnb? Pros and cons - shoot

[Nancy Bachety]

For tax purposes Airbnb wants to know if you are a US person or entity (W-9) or if you have a tax ID number (W-8ECI). Income is income regardless but what reasons/benefits would you choose one or other? Liability? I have a tax ID# for an LLC which owns a LTR house but run Airbnb for other houses (that are in my personal name - NOT an LLC) and I'd hesitate to use the same tax ID# for my airbnb business.

Why choose one over the other?