¿Crear un marcador sin agregarlo al mapa?

Puede utilizar LazyMarker.java desde Android Maps Extensions .

No crea físicamente el marcador hasta que usted llama setVisible(true) en él.

Puede hacerlo estableciendo la visibility en false

 Marker marker = mMap.addMarker(new MarkerOptions() .position( new LatLng(arg0.latitude, arg0.longitude)) .draggable(true).visible(false)); 

Editar

 Marker m = new Marker(new z() { @Override public IBinder asBinder() { return null; } @Override public void showInfoWindow() throws RemoteException { } @Override public void setVisible(boolean paramBoolean) throws RemoteException { } @Override public void setTitle(String paramString) throws RemoteException { } @Override public void setSnippet(String paramString) throws RemoteException { } @Override public void setPosition(LatLng paramLatLng) throws RemoteException { } @Override public void setDraggable(boolean paramBoolean) throws RemoteException { } @Override public void remove() throws RemoteException { } @Override public boolean isVisible() throws RemoteException { return false; } @Override public boolean isInfoWindowShown() throws RemoteException { return false; } @Override public boolean isDraggable() throws RemoteException { return false; } @Override public void hideInfoWindow() throws RemoteException { } @Override public int hashCodeRemote() throws RemoteException { return 0; } @Override public String getTitle() throws RemoteException { return null; } @Override public String getSnippet() throws RemoteException { return null; } @Override public LatLng getPosition() throws RemoteException { return null; } @Override public String getId() throws RemoteException { return null; } @Override public boolean g(z paramz) throws RemoteException { return false; } }); 

Y luego agregarlo cuando quieras así

 mMap.addMarker(new MarkerOptions().position((m.getPosition()))); 

Espero eso ayude