Variable Assigned Error along with "Name "" Not Assigned in Current Context

Hi, I'm using GetComponent to grab a bool from this script:

 using UnityEngine;
 using System.Collections;
 
 public class GameObjectDisable : MonoBehaviour {
     public Material PlaceRed;
     public Material PlaceGreen;
     public bool CanPlace;
 
     void Start (){
         GameObject GhostObject = GameObject.Find("planetstationtransparent(Clone)");
     }
 
     void OnCollisionEnter (Collision col) { //if in contact, change to red and make non placeable
         if(col.gameObject.name == "planetstationtransparent(Clone)")
         {
             GhostObject.GetComponent<Renderer>().material = PlaceRed;
             bool CanPlace = false;
         }
     }
     void OnCollisionExit(Collision col) { //if no longer in contact, change back to green and placeable
         if(col.gameObject.name == "planetstationtransparent(Clone)")
         {
             GhostObject.GetComponent<Renderer>().material = PlaceGreen;
             bool CanPlace = true;
         }
     }
 }

 And use it to see if it can pass the if statement in this script.
 
 
 using UnityEngine;
 using UnityEngine.Events;
 using System.Collections;
 
 public class Builder : MonoBehaviour {
      
      public GameObject BuildingFinal;
      public GameObject GhostObject;
      public Builder BuilderToggle;
      
 
 
     // Use this for initialization
     void Start () {
         GameObject Water = GameObject.FindWithTag("Water");
         //grabs itself so it can be disabled in the future
         BuilderToggle = GetComponent<Builder>();
         //makes translucent object with red and half opacity TODO: GET THIS TO WORK
         GhostObject = (GameObject)Instantiate(Resources.Load("planetstationtransparent"));
     }
     
     // Update is called once per frame
     void Update () {
         
         //re-enables the object if previously disabled 
          GhostObject.SetActive(true);
          Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
          RaycastHit hit;
          
          if(Physics.Raycast(ray, out hit)){
              Vector3 Placement = hit.point;
              GhostObject.transform.position = Placement;
              GhostObject.transform.up = hit.normal; 
             //transform up is for rotation
             
             // previous code is for the raycasting of planet mesh
             if (Input.GetMouseButtonDown(0) && Water.GetComponent<GameObjectDisable>().CanPlace == true) {
                 BuildingFinal = (GameObject)Instantiate(Resources.Load("planetstation"));
                 BuildingFinal.transform.position = Placement;
                 BuilderToggle.enabled = false;
                 
          }
             if (Input.GetMouseButtonDown(1)){
                 GhostObject.SetActive(false);
                 BuilderToggle.enabled = false;
             }
         }
         
     }
 }

I posted the entire code because I'm not sure where the error lies. The first script goes on the Water GameObject, declaring that if it is in contact, make it not placeable, and Red