gistfile1.txt

add_filter( "houzez_property_feed_properties_due_import_reaxml", 'lowercase_suburb', 10, 2 );
function lowercase_suburb( $properties, $import_id )
{
    foreach ( $properties as $property )
    {
        if ( isset($property->address->suburb) )
        {
            $property->address->suburb = ucwords(strtolower((string)$property->address->suburb));
        }
    }
    return $properties;
}