Passing results of a value from one method to another

I have a method below which i need to use the results of and pass the value of the below to another method:
       public void RetrieveByPIN(String searchPIN)

        {
            //will only be one letter per daily pack
            BusinessEntityCollection fulfilmentRequestCollection = Communicate.Instance.RetrieveByValue(EntityName.fulfilment_request, "pin", searchPIN);
            if (fulfilmentRequestCollection.BusinessEntities.Length > 0)
            {
                fulfilmentRequest = (fulfilment_request)fulfilmentRequestCollection.BusinessEntities[0];
 & ...