@ManyToMany(cascade = CascadeType.ALL)
    @JoinTable(
            name = "t_reservations",
            joinColumns = @JoinColumn(name = "customer_id", referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "apartment_id", referencedColumnName = "id"),
            foreignKey = @ForeignKey(name = "FK_reservation_customer"),
            inverseForeignKey = @ForeignKey(name = "FK_reservation_apartment")
    )
    private List<ApartmentEntity> reserved;

    @ManyToMany(cascade = CascadeType.ALL)
    @JoinTable(
            name = "t_purchases",
            joinColumns = @JoinColumn(name = "customer_id", referencedColumnName = "id"),
            inverseJoinColumns = @JoinColumn(name = "apartment_id", referencedColumnName = "id"),
            foreignKey = @ForeignKey(name = "FK_purchase_customer"),
            inverseForeignKey = @ForeignKey(name = "FK_purchase_apartment")
    )
    private List<ApartmentEntity> purchased;