"I want to create my own additonal account at this address"

Ive recently moved into a basement apartment and Ive been trying to get internet service, however the upstairs tenants also use xfinity. Does the option "No, I want to create my own additional account at this address."

still keep the original service? The address however doesnt have a unique identifier even though the unit has its own utilities and coax jack. Its my only good option for internet in my area