The devices wouldn’t know of each other, so the hardware is fine with this.
If you have streaming services (VOD or linear [live] streaming TV) linked to the accounts on those devices, then those may have limits that may apply. The limits may differ per service. Some may work for one address, some assume one of the addresses to get a sense of “local stations”, some may allow service on 2 screens simultaneously, or 3 screens, or 4 screens, or 6 screens. Some may have subscription tiers for the number of screens that you need. Often the numbers of screens will refer to devices including mobile. Fixed devices like TVs and streaming devices connected to a TV would require the same household (residence).
E.g. Disney+ allows for 4 devices simultaneously, but within one household (internet connection). They won’t allow you to share this one subscription in three properties. Likewise, a Hulu subscription is intended for a single residence.
Likewise, a Netflix subscription is intended for a single residence.
So what did you intend to include in the Apple TV box for the guests, if anything? Linear (live) TV would likely require 3 separate plans. Just the box alone wouldn’t give them much, although they may sign in with their own account(s) for some VOD services. And hopefully they remember to sign out when they leave [expect after-the-fact calls about that].