@Angelica-Y-Jorge0 Ensure the extra guests stay outside? The host is supposed to stand there policing that?
Presumably they would need to use the bathroom. Get a drink of water. Then they'll have beers in the fridge they'll be going in and out for. Etc, etc.
In any case, these people cancelled. Not everything is worth extra revenue. These people would have been bad news, I think. They waited til after the booking was confirmed to ask about the photo shoot, when it seems being told no was a deal breaker. So if that was crucial, why didn't they inquire first? They asked for 1 night when the host specifies minimum 2. And 3 guys overnight pre-wedding? Sure to be a party. And more would have shown up, maybe not to sleep there, but to party.