diff --git a/Models/Answer.php b/Models/Answer.php
index 247cb65..d23de07 100644
--- a/Models/Answer.php
+++ b/Models/Answer.php
@@ -49,67 +49,67 @@ class Answer
      */
     private string $description = '';
 
-    private static $instances = [];
-
-    public function getInstance($id)
-    {
-        if (!isset(self::$instances[$id])) {
-            self::$instances[$id] = new self($id);
-        }
-
-        return self::$instances[$id];
-    }
-
-    public function init($id) : void
-    {
-    }
-
-    public function __clone()
-    {
-    }
-
-    public function getId()
+    /**
+     * Get model id.
+     *
+     * @return int
+     *
+     * @since 1.0.0
+     */
+    public function getId() : int
     {
         return $this->id;
     }
 
-    public function getName()
+    /**
+     * Get answer name/title.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getName() : string
     {
         return $this->name;
     }
 
-    public function setName($name) : void
+    /**
+     * Get name/title.
+     *
+     * @param string $name Name/title
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setName(string $name) : void
     {
         $this->name = $name;
     }
 
-    public function getDescription()
+    /**
+     * Get description.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getDescription() : string
     {
         return $this->description;
     }
 
-    public function setDescription($desc) : void
+    /**
+     * Set description.
+     *
+     * @param string $desc Description
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setDescription(string $desc) : void
     {
         $this->description = $desc;
     }
-
-    public function delete() : void
-    {
-    }
-
-    public function create() : void
-    {
-    }
-
-    public function update() : void
-    {
-    }
-
-    public function serialize() : void
-    {
-    }
-
-    public function unserialize($data) : void
-    {
-    }
 }
diff --git a/Models/Question.php b/Models/Question.php
index 886597a..e208332 100644
--- a/Models/Question.php
+++ b/Models/Question.php
@@ -49,67 +49,67 @@ class Question
      */
     private string $description = '';
 
-    private static $instances = [];
-
-    public function getInstance($id)
-    {
-        if (!isset(self::$instances[$id])) {
-            self::$instances[$id] = new self($id);
-        }
-
-        return self::$instances[$id];
-    }
-
-    public function init($id) : void
-    {
-    }
-
-    public function __clone()
-    {
-    }
-
-    public function getId()
+    /**
+     * Get id.
+     *
+     * @return int
+     *
+     * @since 1.0.0
+     */
+    public function getId() : int
     {
         return $this->id;
     }
 
-    public function getName()
+    /**
+     * Get name/title.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getName() : string
     {
         return $this->name;
     }
 
-    public function setName($name) : void
+    /**
+     * Set name/title.
+     *
+     * @param string $name Name/title
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setName(string $name) : void
     {
         $this->name = $name;
     }
 
-    public function getDescription()
+    /**
+     * Get string.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getDescription() : string
     {
         return $this->description;
     }
 
+    /**
+     * Set description.
+     *
+     * @param string $desc Description
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setDescription($desc) : void
     {
         $this->description = $desc;
     }
-
-    public function delete() : void
-    {
-    }
-
-    public function create() : void
-    {
-    }
-
-    public function update() : void
-    {
-    }
-
-    public function serialize() : void
-    {
-    }
-
-    public function unserialize($data) : void
-    {
-    }
 }
diff --git a/Models/Section.php b/Models/Section.php
index 48880e4..b09d94b 100644
--- a/Models/Section.php
+++ b/Models/Section.php
@@ -49,85 +49,67 @@ class Section
      */
     private string $description = '';
 
-    private static $instances = [];
-
-    public function getInstance($id)
-    {
-        if (!isset(self::$instances[$id])) {
-            self::$instances[$id] = new self($id);
-        }
-
-        return self::$instances[$id];
-    }
-
-    public function getId()
+    /**
+     * Get id.
+     *
+     * @return int
+     *
+     * @since 1.0.0
+     */
+    public function getId() : int
     {
         return $this->id;
     }
 
-    public function getName()
+    /**
+     * Get name.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getName() : string
     {
         return $this->name;
     }
 
-    public function setName($name) : void
-    {
-        $this->name = $name;
-    }
-
-    public function getDescription()
-    {
-        return $this->description;
-    }
-
-    public function setDescription($desc) : void
-    {
-        $this->description = $desc;
-    }
-
-    public function delete() : void
-    {
-    }
-
-    public function create() : void
-    {
-    }
-
-    public function update() : void
-    {
-    }
-
-    public function serialize() : void
-    {
-    }
-
-    public function unserialize($data) : void
-    {
-    }
-
     /**
-     * Init object by ID.
+     * Set name.
      *
-     * This usually happens from DB or cache
-     *
-     * @param int $id Object ID
+     * @param string $name Name
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function init($id) : void
+    public function setName(string $name) : void
     {
-        // TODO: Implement init() method.
+        $this->name = $name;
     }
 
     /**
-     * Overwriting clone in order to maintain singleton pattern.
+     * Get description.
+     *
+     * @return string
      *
      * @since 1.0.0
      */
-    public function __clone()
+    public function getDescription() : string
     {
-        // TODO: Implement __clone() method.
+        return $this->description;
+    }
+
+    /**
+     * Set description.
+     *
+     * @param string $desc Description
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setDescription(string $desc) : void
+    {
+        $this->description = $desc;
     }
 }
diff --git a/Models/Survey.php b/Models/Survey.php
index df785fb..55ba94d 100644
--- a/Models/Survey.php
+++ b/Models/Survey.php
@@ -52,10 +52,10 @@ class Survey
     /**
      * Created.
      *
-     * @var   datetime
+     * @var   \DateTime
      * @since 1.0.0
      */
-    private $created = null;
+    private \DateTime $created;
 
     /**
      * Creator.
@@ -65,87 +65,127 @@ class Survey
      */
     private ?int $creator = null;
 
-    private static $instances = [];
-
-    public function getInstance($id)
+    /**
+     * Constructor.
+     *
+     * @since 1.0.0
+     */
+    public function __construct()
     {
-        if (!isset(self::$instances[$id])) {
-            self::$instances[$id] = new self($id);
-        }
-
-        return self::$instances[$id];
+        $this->created = new \DateTime('now');
     }
 
-    public function init($id) : void
-    {
-    }
-
-    public function __clone()
-    {
-    }
-
-    public function getId()
+    /**
+     * Get id.
+     *
+     * @return int
+     *
+     * @since 1.0.0
+     */
+    public function getId() : int
     {
         return $this->id;
     }
 
-    public function getName()
+    /**
+     * Get name/title.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getName() : string
     {
         return $this->name;
     }
 
-    public function setName($name) : void
+    /**
+     * Set name/title.
+     *
+     * @param string $name Name/title
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setName(string $name) : void
     {
         $this->name = $name;
     }
 
-    public function getDescription()
+    /**
+     * Get description.
+     *
+     * @return string
+     *
+     * @since 1.0.0
+     */
+    public function getDescription() : string
     {
         return $this->description;
     }
 
-    public function setDescription($desc) : void
+    /**
+     * Set description.
+     *
+     * @param string $desc Description
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
+    public function setDescription(string $desc) : void
     {
         $this->description = $desc;
     }
 
-    public function getCreated()
+    /**
+     * Get created.
+     *
+     * @return \DateTime
+     *
+     * @since 1.0.0
+     */
+    public function getCreated() : \DateTime
     {
         return $this->created;
     }
 
+    /**
+     * Set created.
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setCreated($created) : void
     {
         $this->created = $created;
     }
 
+    /**
+     * Get creator.
+     *
+     * @return mixed
+     *
+     * @since 1.0.0
+     */
     public function getCreator()
     {
         return $this->creator;
     }
 
+    /**
+     * Set creator.
+     *
+     * @param mixed $creator Creator
+     *
+     * @return void
+     *
+     * @since 1.0.0
+     */
     public function setCreator($creator) : void
     {
         $this->creator = $creator;
     }
-
-    public function delete() : void
-    {
-    }
-
-    public function create() : void
-    {
-    }
-
-    public function update() : void
-    {
-    }
-
-    public function serialize() : void
-    {
-    }
-
-    public function unserialize($data) : void
-    {
-    }
 }