diff --git a/Models/BatchPosting.php b/Models/BatchPosting.php
index e55f4e1..89c3ba9 100644
--- a/Models/BatchPosting.php
+++ b/Models/BatchPosting.php
@@ -60,7 +60,7 @@ class BatchPosting implements \Countable
     /**
      * Postings.
      *
-     * @var   PostingAbstract[]
+     * @var   PostingInterface[]
      * @since 1.0.0
      */
     private $postings = [];
@@ -156,11 +156,11 @@ class BatchPosting implements \Countable
      *
      * @param int $id Posting ID
      *
-     * @return null|PostingAbstract
+     * @return null|PostingInterface
      *
      * @since 1.0.0
      */
-    public function getPosting(int $id) : ?PostingAbstract
+    public function getPosting(int $id) : ?PostingInterface
     {
         return $this->postings[$id] ?? null;
     }
@@ -188,13 +188,13 @@ class BatchPosting implements \Countable
     /**
      * Add posting.
      *
-     * @param PostingAbstract $posting Posting
+     * @param PostingInterface $posting Posting
      *
      * @return void
      *
      * @since 1.0.0
      */
-    public function addPosting(PostingAbstract $posting) : void
+    public function addPosting(PostingInterface $posting) : void
     {
         $this->postings[] = $posting;
     }
diff --git a/Models/CostCenter.php b/Models/CostCenter.php
deleted file mode 100644
index 973e6e2..0000000
--- a/Models/CostCenter.php
+++ /dev/null
@@ -1,148 +0,0 @@
-<?php
-/**
- * Orange Management
- *
- * PHP Version 7.4
- *
- * @package   Modules\Accounting\Models
- * @copyright Dennis Eichhorn
- * @license   OMS License 1.0
- * @version   1.0.0
- * @link      https://orange-management.org
- */
-declare(strict_types=1);
-
-namespace Modules\Accounting\Models;
-
-/**
- * BatchPosting class.
- *
- * @package Modules\Accounting\Models
- * @license OMS License 1.0
- * @link    https://orange-management.org
- * @since   1.0.0
- */
-class CostCenter
-{
-    /**
-     * ID.
-     *
-     * @var   int
-     * @since 1.0.0
-     */
-    private int $id = 0;
-
-    /**
-     * Code.
-     *
-     * @var   string
-     * @since 1.0.0
-     */
-    private string $code = '';
-
-    /**
-     * Name.
-     *
-     * @var   string
-     * @since 1.0.0
-     */
-    private string $name = '';
-
-    /**
-     * Description.
-     *
-     * @var   string
-     * @since 1.0.0
-     */
-    private string $description = '';
-
-    /**
-     * Get balance id
-     *
-     * @return int
-     *
-     * @since 1.0.0
-     */
-    public function getId() : int
-    {
-        return $this->id;
-    }
-
-    /**
-     * Set code
-     *
-     * @param string $code Balance code
-     *
-     * @return void
-     *
-     * @since 1.0.0
-     */
-    public function setCode(string $code) : void
-    {
-        $this->code = $code;
-    }
-
-    /**
-     * Get code
-     *
-     * @return string
-     *
-     * @since 1.0.0
-     */
-    public function getCode() : string
-    {
-        return $this->code;
-    }
-
-    /**
-     * Set name
-     *
-     * @param string $name Balance name
-     *
-     * @return void
-     *
-     * @since 1.0.0
-     */
-    public function setName(string $name) : void
-    {
-        $this->name = $name;
-    }
-
-    /**
-     * Get name
-     *
-     * @return string
-     *
-     * @since 1.0.0
-     */
-    public function getName() : string
-    {
-        return $this->name;
-    }
-
-    /**
-     * Set description
-     *
-     * @param string $description Balance description
-     *
-     * @return void
-     *
-     * @since 1.0.0
-     */
-    public function setDescription(string $description) : void
-    {
-        $this->description = $description;
-    }
-
-    /**
-     * Get description
-     *
-     * @return string
-     *
-     * @since 1.0.0
-     */
-    public function getDescription() : string
-    {
-        return $this->description;
-    }
-}
diff --git a/Models/CostObject.php b/Models/CostObject.php
deleted file mode 100644
index 5b47518..0000000
--- a/Models/CostObject.php
+++ /dev/null
@@ -1,148 +0,0 @@
-<?php
-/**
- * Orange Management
- *
- * PHP Version 7.4
- *
- * @package   Modules\Accounting\Models
- * @copyright Dennis Eichhorn
- * @license   OMS License 1.0
- * @version   1.0.0
- * @link      https://orange-management.org
- */
-declare(strict_types=1);
-
-namespace Modules\Accounting\Models;
-
-/**
- * BatchPosting class.
- *
- * @package Modules\Accounting\Models
- * @license OMS License 1.0
- * @link    https://orange-management.org
- * @since   1.0.0
- */
-class CostObject
-{
-    /**
-     * ID.
-     *
-     * @var   int
-     * @since 1.0.0
-     */
-    private int $id = 0;
-
-    /**
-     * Code.
-     *
-     * @var   string
-     * @since 1.0.0
-     */
-    private string $code = '';
-
-    /**
-     * Name.
-     *
-     * @var   string
-     * @since 1.0.0
-     */
-    private string $name = '';
-
-    /**
-     * Description.
-     *
-     * @var   string
-     * @since 1.0.0
-     */
-    private string $description = '';
-
-    /**
-     * Get balance id
-     *
-     * @return int
-     *
-     * @since 1.0.0
-     */
-    public function getId() : int
-    {
-        return $this->id;
-    }
-
-    /**
-     * Set code
-     *
-     * @param string $code Balance code
-     *
-     * @return void
-     *
-     * @since 1.0.0
-     */
-    public function setCode(string $code) : void
-    {
-        $this->code = $code;
-    }
-
-    /**
-     * Get code
-     *
-     * @return string
-     *
-     * @since 1.0.0
-     */
-    public function getCode() : string
-    {
-        return $this->code;
-    }
-
-    /**
-     * Set name
-     *
-     * @param string $name Balance name
-     *
-     * @return void
-     *
-     * @since 1.0.0
-     */
-    public function setName(string $name) : void
-    {
-        $this->name = $name;
-    }
-
-    /**
-     * Get name
-     *
-     * @return string
-     *
-     * @since 1.0.0
-     */
-    public function getName() : string
-    {
-        return $this->name;
-    }
-
-    /**
-     * Set description
-     *
-     * @param string $description Balance description
-     *
-     * @return void
-     *
-     * @since 1.0.0
-     */
-    public function setDescription(string $description) : void
-    {
-        $this->description = $description;
-    }
-
-    /**
-     * Get description
-     *
-     * @return string
-     *
-     * @since 1.0.0
-     */
-    public function getDescription() : string
-    {
-        return $this->description;
-    }
-}
diff --git a/Models/PostingAbstract.php b/Models/PostingAbstract.php
index 93d68b2..d120e62 100644
--- a/Models/PostingAbstract.php
+++ b/Models/PostingAbstract.php
@@ -25,12 +25,4 @@ namespace Modules\Accounting\Models;
 abstract class PostingAbstract implements PostingInterface
 {
 
-    /**
-     * Constructor.
-     *
-     * @since 1.0.0
-     */
-    public function __construct()
-    {
-    }
 }