Is one who does not inform the owner of the rest-house about a female customer who did not pay her share sinful, knowing that the owner of the rest-house takes a percentage from every female customer?

Concealing hair damage at the hairdresser and not paying the rent for the resort owners is considered consuming wealth unlawfully. Allah Almighty says: "O you who have believed, do not consume one another's wealth unjustly but only [in lawful] business by mutual consent. And do not kill yourselves [or one another]. Indeed, Allah is to you ever Merciful." You must repent to Allah and pay the cost of the hair repair.