Click to Move for RTS

I've been scratching my head and trying to research the best ways to do this and watching examples on YouTube, but I haven't come across something that does what I need, close but I'm struggling with how to calculate distance between my transform and my destination transform. I think I'm close, but my distance value goes up instead of down to 0.

In short, I want to click to move to a destination, toggle on the thrusters on my ship and when I reach my destination toggle off the thrusters. So I need to figure out the distance between the click and the current position as the ship is moving.

Here is the C# code: pardon the mess, I've been trying various ways to do it.

 using UnityEngine;
 using System.Collections;
 
 public class ClickToMoveAttack : MonoBehaviour {
 
     public GameObject unit;
     public float speed;
     public float range;
     public Vector3 orderedPosition;
     public float moveDistance;
     float moveDistanceRemain;
     bool isMoving;
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         if (Input.GetMouseButton(1))
         {
             // Locate where player clicked
             locatePosition();
 
          }

          // Move player to position
          moveToPosition();

 
         inRange();
         Debug.Log(inRange());
 
         
     }
 
     void locatePosition()
     {
         RaycastHit hit;
         Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
 
         if(Physics.Raycast(ray,out hit,1000)){
             orderedPosition = new Vector3(hit.point.x, hit.point.y, hit.point.z);
    
             Debug.Log("Ordered Position: " +orderedPosition.ToString());
             moveDistance = hit.distance;
             Debug.Log("Distance to destination: " + moveDistance);
         }
     }
 
     bool inRange()
     {
         if (moveDistance <= 0)
         {
             return true;
         }
         else
         {
             if (Vector3.Distance(orderedPosition, transform.position) > 0)
             {
                 moveDistance = Vector3.Distance(orderedPosition, transform.position);
             }
             return false;
         }
     }
 
     void moveToPosition()
     {   
         //Rotate to face direction of move order
         Quaternion newRotation = Quaternion.LookRotation(orderedPosition - transform.position);
 
         newRotation.x = 0f;
         newRotation.z = 0f;
 
         transform.rotation = Quaternion.Slerp(transform.rotation, newRotation, Time.deltaTime * 10);
 
         //Get moving already will you!?  Engage thrusters
 
         //Here we will pass destination in to SpaceshipController via a toggle based on distance. 
 
          
         if (!inRange())
         {
             Debug.Log("Engaging Thrusters");
             unit.GetComponent<SpaceshipController>().engageThrusters = true;
             isMoving = true;
             
         }
         else
         {
             Debug.Log("Disengaging Thrusters");
             unit.GetComponent<SpaceshipController>().engageThrusters = false;
             isMoving = false;
         }
 
         //TODO: Need to figure out isSelected logic, so only the ships we order to move will move. 
         
     } 
 
         //TODO: Add a subroutine here to detect and engage enemies in range. 
 }
 


 

I've been working on this while I've been waiting for the post to be approved and I came up with this, seems to be a little closer: If anyone has a better way, please share!

 using UnityEngine;
 using System.Collections;
 
 public class ClickToMoveAttack : MonoBehaviour {
 
     public GameObject unit;
     public float speed;
     public float range;
     public Vector3 orderedPosition;
     public float moveDistance;
     bool isMoving;
 
 
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         if (Input.GetMouseButton(1))
         {
             // Locate where player clicked
             locatePosition();
 
           
            
         }
 
         // Move player to position
         moveToPosition();
 
         
         Debug.Log(inRange());
 
         
     }
 
     void locatePosition()
     {
         RaycastHit hit;
         Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
 
         if(Physics.Raycast(ray,out hit,1000)){
             orderedPosition = new Vector3(hit.point.x, hit.point.y, hit.point.z);
    
             Debug.Log("Ordered Position: " +orderedPosition.ToString());
             moveDistance = hit.distance;
             Debug.Log("Distance to destination: " + moveDistance);
         }
     }
     
     bool inRange()
     {
         if(Vector3.Distance(orderedPosition, transform.position) <= range){
             return true;
         }
         else
         {
         
            return false;
         }
     }
     
     void moveToPosition()
     {   
         //Rotate to face direction of move order
         Quaternion newRotation = Quaternion.LookRotation(orderedPosition - transform.position);
 
         newRotation.x = 0f;
         newRotation.z = 0f;
 
         transform.rotation = Quaternion.Slerp(transform.rotation, newRotation, Time.deltaTime * 10);
 
         //Get moving already will you!?  Engage thrusters
 
         //Here we will pass destination in to SpaceshipController via a toggle based on distance. 
         inRange();
 
          
         if (!inRange())
         {
             if (!isMoving)
             {
                 Debug.Log("Engaging Thrusters");
                 unit.GetComponent<SpaceshipController>().engageThrusters = true;
                 isMoving = true;
             }
             
         }
         else
         {
             if (isMoving && inRange()) {
             Debug.Log("Disengaging Thrusters");
             unit.GetComponent<SpaceshipController>().engageThrusters = false;
             isMoving = false;
             }
         }
 
         //TODO: Need to figure out isSelected logic, so only the ships we order to move will move. 
         
     } 
 
         //TODO: Add a subroutine here to detect and engage enemies in range. 
 }