Meta Query for Custom field Date

$offerdate = array(
	'relation' => 'AND',
	array(
		'key'     => 'property_available',
		'value'   => 'date',
		'compare' => '<=',
		'type'    => 'DATE',
	),
	array(
		'key'     => 'property_available',
		'compare' => 'EXISTS',
	),
);