How can i set the camera to be automatic behind the player ?

I have a script attached to a camera and the camera follow the player.

 using UnityEngine;
 using System.Collections;
 
 public class CameraFollow : MonoBehaviour
 {
     public GameObject objectToFollow;       //Public variable to store a reference to the player game object
     private Vector3 offset;         //Private variable to store the offset distance between the player and camera
 
     // Use this for initialization
     void Start()
     {
         //Calculate and store the offset value by getting the distance between the player's position and camera's position.
         offset = transform.position - objectToFollow.transform.position;
     }
 
     // LateUpdate is called after Update each frame
     void LateUpdate()
     {
         // Set the position of the camera's transform to be the same as the player's, but offset by the calculated offset distance.
         transform.position = objectToFollow.transform.position + offset;
         transform.LookAt(objectToFollow.transform);
     }
 }

Now instead changing the camera position in the scene view to be behind the player i want to use a bool variable to do it automatic.

So i changed the script to this:

 using UnityEngine;
 using System.Collections;
 
 public class CameraFollow : MonoBehaviour
 {
     public GameObject objectToFollow;       //Public variable to store a reference to the player game object
     public bool behindPlayer = false;
 
     private Vector3 cameraStartPos;
 
     // Use this for initialization
     void Start()
     {
         cameraStartPos = transform.position;
 
         // Put the camera behind the player
         if (behindPlayer == true)
         {
             transform.position = (objectToFollow.transform.position - (objectToFollow.transform.forward * 5) + (objectToFollow.transform.up * 2));
         }
     }
 
     private void Update()
     {
         if (behindPlayer == true)
         {
             transform.position = (objectToFollow.transform.position - (objectToFollow.transform.forward * 5) + (objectToFollow.transform.up * 2));
         }
         else
         {
             transform.position = cameraStartPos;
         }
     }
 
     // LateUpdate is called after Update each frame
     void LateUpdate()
     {
         transform.position = objectToFollow.transform.position;
         transform.LookAt(objectToFollow.transform);
     }
 }

But now i'm not using the offset if it's needed. The line: transform.position = objectToFollow.transform.position; prevent from the variable bool behindPlayer to work. Without this line the camera will follow the player but not like in the script above.

All i want is to add to the first script version a bool variable so i can change the camera position without changing the following script idea.