Template to display widget "Vantage - Home Latest Listings" always in a List view

widget-latest-ad_listing.php

<?php
/**
 * Template to display widget "Vantage - Home Latest Listings".
 *
 * @package Vantage\Templates
 * @since 4.0.0
 */

$items = $instance['items'];
set_query_var( 'listing_layout', 'list' );

?>

<div class="row column">

	<div class="home-widget-head-wrap">
	<?php

	if ( ! empty( $instance['header'] ) ) {
		echo $instance['before_title'] . $instance['header'] . $instance['after_title'];
	}

	if ( ! empty( $instance['description'] ) ) {
		echo '<p class="home-widget-description">' . $instance['description'] . '</p>';
	}

	?>
	</div> <!-- .home-widget-head-wrap -->

	<div class="row listing-wrap small-up-1 medium-up-2 large-up-3">
		<?php while ( $items->have_posts() ) : $items->the_post(); ?>

			<div class="column">
				<?php get_template_part( 'parts/content-item', get_post_type() ); ?>
			</div> <!-- .column -->

		<?php endwhile; ?>
	</div> <!-- .row -->

</div> <!-- .row -->

Copy this file to your child theme, to the parts/ directory.

small-up-1 medium-up-2 large-up-3 - it is how many columns you will see on small, medium and large screens.

small-up-1 - always one column for all screens
small-up-1 medium-up-2 - one column for small screens, two for all other
small-up-1 medium-up-2 large-up-3 - one column for small screens, two for medium, three for large.

Change it how you need.