diff --git a/CHANGELOG.md b/CHANGELOG.md
index ae29f898..1f0a9738 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -35,6 +35,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Show progress as integer for get_scans. [#269](https://github.com/greenbone/ospd/pull/269)
 - Make scan_id attribute mandatory for get_scans. [#270](https://github.com/greenbone/ospd/pull/270)
 - Ignore subsequent SIGINT once inside exit_cleanup(). [#273](https://github.com/greenbone/ospd/pull/273)
+- Simplify start_scan() [#275](https://github.com/greenbone/ospd/pull/275)
 
 ### Fixed
 - Fix stop scan. Wait for the scan process to be stopped before delete it from the process table. [#204](https://github.com/greenbone/ospd/pull/204)
diff --git a/ospd/ospd.py b/ospd/ospd.py
index 6549ca46..88d623cb 100644
--- a/ospd/ospd.py
+++ b/ospd/ospd.py
@@ -505,25 +505,21 @@ def handle_client_stream(self, stream: Stream) -> None:
 
         stream.close()
 
-    def process_finished_hosts(self, scan_id: str, finished_hosts: str) -> None:
+    def process_finished_hosts(self, scan_id: str) -> None:
         """ Process the finished hosts before launching the scans."""
 
+        finished_hosts = self.scan_collection.get_finished_hosts(scan_id)
         if not finished_hosts:
             return
 
         exc_finished_hosts_list = target_str_to_list(finished_hosts)
         self.scan_collection.set_host_finished(scan_id, exc_finished_hosts_list)
 
-    def start_scan(self, scan_id: str, target: Dict) -> None:
+    def start_scan(self, scan_id: str) -> None:
         """ Starts the scan with scan_id. """
         os.setsid()
 
-        if target is None or not target:
-            raise OspdCommandError('Erroneous target', 'start_scan')
-
-        logger.info("%s: Scan started.", scan_id)
-
-        self.process_finished_hosts(scan_id, target.get('finished_hosts'))
+        self.process_finished_hosts(scan_id)
 
         try:
             self.set_scan_status(scan_id, ScanStatus.RUNNING)
@@ -1188,13 +1184,8 @@ def run(self) -> None:
     def start_pending_scans(self):
         for scan_id in self.scan_collection.ids_iterator():
             if self.get_scan_status(scan_id) == ScanStatus.PENDING:
-                scan_target = self.scan_collection.scans_table[scan_id].get(
-                    'target'
-                )
                 scan_func = self.start_scan
-                scan_process = create_process(
-                    func=scan_func, args=(scan_id, scan_target)
-                )
+                scan_process = create_process(func=scan_func, args=(scan_id,))
                 self.scan_processes[scan_id] = scan_process
                 scan_process.start()
                 self.set_scan_status(scan_id, ScanStatus.INIT)
diff --git a/ospd/protocol.py b/ospd/protocol.py
index 6f7d9792..1c04e0fe 100644
--- a/ospd/protocol.py
+++ b/ospd/protocol.py
@@ -47,7 +47,7 @@ class OspRequest:
     @staticmethod
     def process_vts_params(
         scanner_vts: Element,
-    ) -> Dict[str, Union[Dict, List]]:
+    ) -> Dict[str, Union[Dict[str, str], List]]:
         """ Receive an XML object with the Vulnerability Tests an their
         parameters to be use in a scan and return a dictionary.
 
diff --git a/ospd/scan.py b/ospd/scan.py
index 3df8bb4e..3d790651 100644
--- a/ospd/scan.py
+++ b/ospd/scan.py
@@ -22,7 +22,7 @@
 
 from collections import OrderedDict
 from enum import Enum
-from typing import List, Any, Dict, Iterator, Optional, Iterable
+from typing import List, Any, Dict, Iterator, Optional, Iterable, Union
 
 from ospd.network import target_str_to_list
 
@@ -347,7 +347,7 @@ def get_host_count(self, scan_id: str) -> int:
 
         return total_hosts
 
-    def get_ports(self, scan_id: str):
+    def get_ports(self, scan_id: str) -> str:
         """ Get a scan's ports list.
         """
         target = self.scans_table[scan_id].get('target')
@@ -355,30 +355,30 @@ def get_ports(self, scan_id: str):
         self.scans_table[scan_id]['target'] = target
         return ports
 
-    def get_exclude_hosts(self, scan_id: str):
+    def get_exclude_hosts(self, scan_id: str) -> str:
         """ Get an exclude host list for a given target.
         """
         return self.scans_table[scan_id]['target'].get('exclude_hosts')
 
-    def get_finished_hosts(self, scan_id: str):
+    def get_finished_hosts(self, scan_id: str) -> str:
         """ Get the finished host list sent by the client for a given target.
         """
         return self.scans_table[scan_id]['target'].get('finished_hosts')
 
-    def get_credentials(self, scan_id: str):
+    def get_credentials(self, scan_id: str) -> Dict[str, Dict[str, str]]:
         """ Get a scan's credential list. It return dictionary with
         the corresponding credential for a given target.
         """
         return self.scans_table[scan_id]['target'].get('credentials')
 
-    def get_target_options(self, scan_id: str):
+    def get_target_options(self, scan_id: str) -> Dict[str, str]:
         """ Get a scan's target option dictionary.
         It return dictionary with the corresponding options for
         a given target.
         """
         return self.scans_table[scan_id]['target'].get('options')
 
-    def get_vts(self, scan_id: str) -> Dict:
+    def get_vts(self, scan_id: str) -> Dict[str, Union[Dict[str, str], List]]:
         """ Get a scan's vts. """
         scan_info = self.scans_table[scan_id]
         vts = scan_info.pop('vts')