Typical house with a basement, there are about 4-5 renters.

There is a Cat6 line going from my main router to downstairs, which is then connected to a signal booster to give them all wifi.

I’d like to keep the renters completely seperated from my main house home network.

How do I seperate the signal booster/renters from seeing any devices on my main house router?

Should I connect a switch or router in between my main router and the signal booster?

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