Great listing @Tory13
had quick scan of your listing. Can see it is for 2 guests, but in your house rules or anywhere - I may have missed it - but do you state, no additional guests or visitors are permitted to enter the property?
I think only if it is clearly stated would you be able to charge an additional fee.
I appreciate how frustrating it is when guests are so disrespectful, but I’d leave them a negative review. Then sharpen up your house rules and listing. Even state: any additional guests will be required to pay.