going along voluntarily to be questioned by police
 voluntarily appearing for police questioning
 voluntary insurance;  optional insurance;  extra insurance;  vehicle insurance in addition to the basic mandatory insurance
 voluntary liquidation;  winding-up
 private organization (neither controlled nor protected by law);  private organisation
 voluntary questioning (by the police);  voluntary interview
 search conducted with the consent of the party concerned
 off-market real estate sale;  negotiated sale due to loan repayment issues