Custom form value

Hey guys,

I was wondering if it was possible to add a value to query_posts? I have a simple form on my website (www.bayofplenty.info) that has a select box to select the number of bedrooms a property has (which is a custom field) and I’m trying to add it to a results page query with the variable $bedrooms. The form is working fine because I can echo the results, but the query isn’t picking it up.
The query code I’m using is:

<?php $bedrooms = $_POST['bedrooms']; ?>
  <?php $key = '_ct_selectbox_4e4f46f4788f8' ?>
  <?php query_posts('post_type=property&meta_key=$key&meta_value=$bedrooms&posts_per_page=10&orderby=ASC'); ?>
  <?php if (have_posts()) : ?>
  <?php while (have_posts()) : the_post(); ?>
  <?php the_title(); ?>
  <?php the_content(); ?>
  <?php endwhile; ?>
  <?php else: ?>
  Sorry, no results were found for your search.
  <?php endif; ?>