sale price

saleprice = array(
	'relation' => 'AND',
	array(
		'key'     => 'sale_price',
		'value'   => '15',
		'compare' => '<',
		'type'    => 'NUMERIC',
	),
	array(
		'key'     => 'sale_price',
		'compare' => 'EXISTS',
	),
);