Meta_query not filtering posts

I think you don’t have to use meta_query.

Simply use the code like shown below:

$args = array(
        'post_type' => 'property',
        'meta_key' => 'rental_type',
        'meta_value' => 'Vacation'
        'posts_per_page' => $properties_per_page,
        'paged' => $paged
    );

Also you got to get the value of $properties_per_page before this query.