public IEnumerable <PhoneContact> GetAll(Guid customerId, Guid hostelId) { var phoneContacts = _phoneContactRepository.List().Where(a => a.CustomerId == customerId); var customersIds = _customerRepository.List().Where(a => a.HostelKey == hostelId).Select(a => a.Id).ToList(); var hostelPhoneContacts = _phoneContactRepository.List().Where(a => customersIds.Contains(a.CustomerId) && a.Type == PhoneContactType.Local); return(phoneContacts.Concat(hostelPhoneContacts.Except(phoneContacts))); }