diff --git a/base-map/src/main/java/ru/touchin/basemap/MapExtension.kt b/base-map/src/main/java/ru/touchin/basemap/MapExtension.kt
index a78589d..0bde807 100644
--- a/base-map/src/main/java/ru/touchin/basemap/MapExtension.kt
+++ b/base-map/src/main/java/ru/touchin/basemap/MapExtension.kt
@@ -2,34 +2,12 @@ package ru.touchin.basemap
 
 import android.util.SparseArray
 
-inline fun <K, V> MutableMap<K, V>.getOrPutIfNotNull(key: K, defaultValue: () -> V?): V? {
-    val value = get(key)
-    return if (value == null) {
-        val value = defaultValue()
-        when {
-            value != null -> {
-                put(key, value)
-                value
-            }
-            else -> null
+inline fun <K, V> MutableMap<K, V>.getOrPutIfNotNull(key: K, defaultValue: () -> V?): V? =
+        get(key) ?: defaultValue()?.also { value ->
+            put(key, value)
         }
-    } else {
-        value
-    }
-}
 
-inline fun <V> SparseArray<V>.getOrPutIfNotNull(key: Int, defaultValue: () -> V?): V? {
-    val value = get(key)
-    return if (value == null) {
-        val value = defaultValue()
-        when {
-            value != null -> {
-                put(key, value)
-                value
-            }
-            else -> null
+inline fun <V> SparseArray<V>.getOrPutIfNotNull(key: Int, defaultValue: () -> V?): V? =
+        get(key) ?: defaultValue()?.also { value ->
+            put(key, value)
         }
-    } else {
-        value
-    }
-}
diff --git a/google-map/src/main/java/ru/touchin/googlemap/GoogleIconGenerator.kt b/google-map/src/main/java/ru/touchin/googlemap/GoogleIconGenerator.kt
index 69f9917..d29c67c 100644
--- a/google-map/src/main/java/ru/touchin/googlemap/GoogleIconGenerator.kt
+++ b/google-map/src/main/java/ru/touchin/googlemap/GoogleIconGenerator.kt
@@ -40,11 +40,9 @@ open class GoogleIconGenerator<T : ClusterItem>(
                 BitmapDescriptorFactory.fromBitmap(it.toBitmap())
             }
 
-    override fun getClusterItemView(clusterItem: T) = clusterItemIconsCache.getOrPutIfNotNull(clusterItem) {
-        getClusterItemIcon(clusterItem)
-    }
+    override fun getClusterItemView(clusterItem: T): BitmapDescriptor? =
+            clusterItemIconsCache.getOrPutIfNotNull(clusterItem) { getClusterItemIcon(clusterItem) }
 
-    override fun getClusterView(cluster: Cluster<T>) = clusterIconsCache.getOrPutIfNotNull(cluster.size) {
-        getClusterIcon(cluster)
-    }
+    override fun getClusterView(cluster: Cluster<T>): BitmapDescriptor? =
+            clusterIconsCache.getOrPutIfNotNull(cluster.size) { getClusterIcon(cluster) }
 }
diff --git a/google-map/src/main/java/ru/touchin/googlemap/GooglePlacemarkManager.kt b/google-map/src/main/java/ru/touchin/googlemap/GooglePlacemarkManager.kt
index 61d01d6..14b3518 100644
--- a/google-map/src/main/java/ru/touchin/googlemap/GooglePlacemarkManager.kt
+++ b/google-map/src/main/java/ru/touchin/googlemap/GooglePlacemarkManager.kt
@@ -158,7 +158,7 @@ class GooglePlacemarkManager<TClusterItem : ClusterItem>(
         onCameraIdleListener = listener
     }
 
-    companion object {
+    private companion object {
         const val CAMERA_DEBOUNCE_MILLI = 50L
 
         const val CLUSTERING_START_DEBOUNCE_MILLI = 50L
diff --git a/yandex-map/src/main/java/ru/touchin/yandexmap/YandexIconGenerator.kt b/yandex-map/src/main/java/ru/touchin/yandexmap/YandexIconGenerator.kt
index 827961d..13c2b41 100644
--- a/yandex-map/src/main/java/ru/touchin/yandexmap/YandexIconGenerator.kt
+++ b/yandex-map/src/main/java/ru/touchin/yandexmap/YandexIconGenerator.kt
@@ -10,13 +10,11 @@ abstract class YandexIconGenerator<TPoint : PointModel>
     private val placemarksCache = mutableMapOf<TPoint, ViewProvider>()
     private val clustersCache = mutableMapOf<List<TPoint>, ViewProvider>()
 
-    override fun getClusterItemView(clusterItem: TPoint) = placemarksCache.getOrPutIfNotNull(clusterItem) {
-        getClusterItemIcon(clusterItem)
-    }
+    override fun getClusterItemView(clusterItem: TPoint): ViewProvider? =
+            placemarksCache.getOrPutIfNotNull(clusterItem) { getClusterItemIcon(clusterItem) }
 
-    override fun getClusterView(cluster: List<TPoint>) = clustersCache.getOrPutIfNotNull(cluster) {
-        getClusterIcon(cluster)
-    }
+    override fun getClusterView(cluster: List<TPoint>): ViewProvider? =
+            clustersCache.getOrPutIfNotNull(cluster) { getClusterIcon(cluster) }
 
     abstract override fun getClusterIcon(cluster: List<TPoint>): ViewProvider?
 
diff --git a/yandex-map/src/main/java/ru/touchin/yandexmap/YandexPlacemarkManager.kt b/yandex-map/src/main/java/ru/touchin/yandexmap/YandexPlacemarkManager.kt
index c5f0f73..ad62bd4 100644
--- a/yandex-map/src/main/java/ru/touchin/yandexmap/YandexPlacemarkManager.kt
+++ b/yandex-map/src/main/java/ru/touchin/yandexmap/YandexPlacemarkManager.kt
@@ -28,6 +28,8 @@ class YandexPlacemarkManager<TPoint : PointModel>(
             clusterRadius: Double = 42.0,
             minZoom: Int = 35
     ) {
+        removeMarkers()
+
         val clusterizedCollection = mapView.map.mapObjects.addClusterizedPlacemarkCollection(this)
         val addedPlacemarks = clusterizedCollection.addEmptyPlacemarks(markers.map { it.point })