Cake newbie question: values from another table in a view

[JamieJelly]

I am new to using cake and am having difficulty at one of the first hurdles of my first application (outside of all the tutorials I've done!)

I have three models:
Property
Dealers
Photos

Dealers have many properties, properties have many photos.

Through reusing code from a tutorial, when adding a property, I can get a dropdown of all the dealers. The code looks something like this:

<?php
class PropertiesController extends AppController {

    var $name = 'Properties';
    var $helpers = array('Html', 'Form' );

    function index() {
        ...
    }

    function add() {
        if (empty($this->data)) {
            $this->set('dealers', $this->Property->Dealer->generateList());
            $this->render();
        } else {
            // create property
            }
        }
    }

However, when I try and reuse similar code in the Photos controller, such as this:

<?php

class PhotosController extends AppController {
    var $name = 'Photos';
    var $helpers = array('Html', 'Form' );
    
    function add()
    {
        if (empty($this->data)) {
        $this->set('properties', $this->Property->Property->generateList());
        $this->render();
        }
        else
        {
            // add photo
        }
    }
    
}
?>

I get horrific errors like this:

Notice: Undefined property: PhotosController::$Property in /Applications/MAMP/htdocs/property_inv/app/controllers/photos_controller.php on line 9

Notice: Trying to get property of non-object in /Applications/MAMP/htdocs/property_inv/app/controllers/photos_controller.php on line 9

Fatal error: Call to a member function generateList() on a non-object in /Applications/MAMP/htdocs/property_inv/app/controllers/photos_controller.php on line 9

Can anyone help me overcome this?

Many thanks!