diff --git a/Assets/Scripts/Drag&Drop/ObjectPlaceholder.cs b/Assets/Scripts/Drag&Drop/ObjectPlaceholder.cs
index 781c2fe..af2357d 100644
--- a/Assets/Scripts/Drag&Drop/ObjectPlaceholder.cs
+++ b/Assets/Scripts/Drag&Drop/ObjectPlaceholder.cs
@@ -10,19 +10,40 @@ public class ObjectPlaceholder : UnitPlaceholder
     }
     public override bool CanBePlacedHere()
     {
+        //bool isTileEmpty = !LevelManager.Instance.Has<ILevelObject>(obj => obj.Position.IsContainedIn(transform.position));
+        bool isHarvesterAndAllowed = IsHarvesterAndAllowed();
+
         var objsOnPosition = LevelManager.Instance.GetAll<ILevelObject>(obj => obj.Position.IsContainedIn(transform.position));
         var positionIsCollidable = objsOnPosition.Exists(obj => obj.IsCollidable);
 
+        // Look if tile is already used by an ally
+        var isTileBusy = false;
+        Transform[] children = LevelManager.Instance.LevelTransform.GetComponentsInChildren<Transform>();
+        foreach (Transform tr in children)
+        {
+            Debug.Log(tr);
+            if (tr == null || tr.tag != "Ally") break;
+            float distance = Vector2.Distance(transform.position, tr.position);
+            Debug.Log("distance : " + distance);
+            if (distance <= 0.5f)
+            {
+                Debug.Log("distance ahah: " + distance);
+                isTileBusy = true;
+                break;
+            }
+        }
+
         var defaultUnitCost = GlobalConfig.Instance.Current.populationCostPerUnit;
-        return !positionIsCollidable 
+        return !positionIsCollidable
             && LevelBoundCache.Contains(transform.position)
             && ResourceManager.Instance.EnoughFor(Rock, Wood, Food)
             && (Prefab.GetComponent<Building>()
-            || ResourceManager.Instance.EnoughPopulationFor(defaultUnitCost)) 
-            && IsFarmerAndAllowed();
+            || ResourceManager.Instance.EnoughPopulationFor(defaultUnitCost))
+            && isHarvesterAndAllowed
+            && !isTileBusy;
     }
 
-    private bool IsFarmerAndAllowed()
+    private bool IsHarvesterAndAllowed()
     {
         Ally unit = Prefab.GetComponent<Ally>();
         
@@ -30,7 +51,6 @@ public class ObjectPlaceholder : UnitPlaceholder
         LevelTile pointedTile = LevelManager.Instance.Get<LevelTile>(obj => obj.Position.IsContainedIn(transform.position));
 
         return unit is not Harvester || (unit is Harvester && IsAllowedTile(pointedTile));
-        //return true;
     }
 
     private bool IsAllowedTile(LevelTile pointedTile)
diff --git a/Assets/Scripts/Drag&Drop/UnitPlaceholder.cs b/Assets/Scripts/Drag&Drop/UnitPlaceholder.cs
index b553a1f..e1b8d46 100644
--- a/Assets/Scripts/Drag&Drop/UnitPlaceholder.cs
+++ b/Assets/Scripts/Drag&Drop/UnitPlaceholder.cs
@@ -11,10 +11,12 @@ public abstract class UnitPlaceholder : DraggablePlaceholder
         WasPlaced?.Invoke(this);
     }
 
+    // This isn't ever used?
     public override bool CanBePlacedHere()
     {
         return base.CanBePlacedHere() && ResourceManager.Instance.EnoughFor(Rock, Wood, Food) 
             && !LevelManager.Instance.Has<ILevelObject>(obj => obj.Position.IsContainedIn(transform.position));
     }
+
     public event System.Action<UnitPlaceholder> WasPlaced;
 }
\ No newline at end of file
diff --git a/Assets/Scripts/General/Extensions.cs b/Assets/Scripts/General/Extensions.cs
index a52cfc7..0208efd 100644
--- a/Assets/Scripts/General/Extensions.cs
+++ b/Assets/Scripts/General/Extensions.cs
@@ -102,7 +102,8 @@ public static class Extensions
     /// <returns></returns>
     public static bool IsContainedIn(this Vector3 vect, Vector3 tilePosition)
     {
-        return Vector2.Distance(vect, tilePosition) < 0.5f;
+        float distance = Vector2.Distance(vect, tilePosition);
+        return distance < 0.5f;
     }
     public static Vector2 RandomInRectangle(float x, float y)
     {
diff --git a/Assets/Scripts/LevelManager/LevelManagerScript.cs b/Assets/Scripts/LevelManager/LevelManagerScript.cs
index 969851e..c162b76 100644
--- a/Assets/Scripts/LevelManager/LevelManagerScript.cs
+++ b/Assets/Scripts/LevelManager/LevelManagerScript.cs
@@ -50,6 +50,7 @@ public class LevelManagerScript : SingletonBehaviour<LevelManagerScript>
     {
         //only when the level is loaded do we start updating
         updateAction = LevelManager.Instance.UpdateLevel;
+        LevelManager.Instance.LevelTransform = transform;
     }
 
     /// <summary>