фильтр записей по категориям и кастомным полям

Всем добрый день, вот мучаюсь над фильтром для записей, фильтр по категориям получилось сделать кое как, только вот по custom field никак, может кто подскажет

<?php
/**
 * The template for displaying all pages.
 *
 * This is the template that displays all pages by default.
 * Please note that this is the WordPress construct of pages
 * and that other 'pages' on your WordPress site will use a
 * different template.
 *

 */

 global $wp_query;
$modifications = array();
if( !empty( $_GET['cat'] ) ) {
	$modifications['meta_query'][] = array(
		'key' => 'cat',
		'value' => $_GET['cat'],
		'compare' => '!='
	);
}

get_header(); ?>

	<div id="primary-mono" class="content-area <?php do_action('tribal_primary-width') ?> page">
		<main id="main" class="site-main" role="main">
			<form action="<?php echo get_permalink(251); ?>" method="get" class="post-filters">

				<select id="selectBox" name="work_type">
					<option value=''><?php _e('work type', 'tribal') ?></option>
					<option value='10' <?php if($_GET['work_type'] == '10'){echo 'selected';} ?>><?php _e('Construction', 'tribal') ?></option>
					<option value='11' <?php if($_GET['work_type'] == '11'){echo 'selected';} ?>><?php _e('Design', 'tribal') ?></option>
					<option value='13' <?php if($_GET['work_type'] == '13'){echo 'selected';} ?>><?php _e('Designing', 'tribal') ?></option>
					<option value='9' <?php if($_GET['work_type'] == '9'){echo 'selected';} ?>><?php _e('Portfolio', 'tribal') ?></option>
				</select>
				<select id="select_status" name="status_type">
					<option value=''><?php _e('status', 'tribal') ?></option>
					<option value='build' <?php if($_GET['status_type'] == 'build'){echo 'selected';} ?>><?php _e('build', 'tribal') ?></option>
					<option value='construction_completed' <?php if($_GET['status_type'] == 'construction_completed'){echo 'selected';} ?>><?php _e('construction completed', 'tribal') ?></option>
				</select>
				<select id="select_location" name="location_type">
					<option value=''><?php _e('location', 'tribal') ?></option>
					<option value=''></option>
					<option value=''></option>
					<option value=''></option>
				</select>
				<select id="select_date" name="date_type">
					<option value=''><?php _e('date', 'tribal') ?></option>
					<option value=''></option>
					<option value=''></option>
					<option value=''></option>
				</select>
				<input type="submit" class="" />
					<div class="buttons"><button class="grid"><p class="icon1"></p><?php _e('Grid', 'tribal') ?></button>
			<button class="list"><p class="icon2"></p><?php _e('List', 'tribal') ?></button>

		</div>
		</form>
		<div id="container">

		 <div class="portfolio-list">
                <ul>
                    <?php
						if(empty($_GET['work_type'])){
							$cats = '10,11,13,9';
						}else{
							$cats = $_GET['work_type'];
						}
                        $paged = ( get_query_var( 'paged' ) ) ? get_query_var( 'paged' ) : 1;
                        $temp = $wp_query;
                        $wp_query= null;
                        $args = array(
                            'paged' => $paged,
                            'post_type' => 'post',
                            'posts_per_page' => '18',
							'cat' => $cats,
                            'orderby' => 'date',
                            'order' => 'DESC',

							);

                        $wp_query = new WP_Query($args);
						if($wp_query->have_posts()):
                        while($wp_query->have_posts()) :
                            $wp_query->the_post();
                    ?>

                    <li>
						<div class="item">
                            <a href="<?php the_permalink(); ?>"><?php the_post_thumbnail(); ?><p><?php the_title(); ?></p></a>

                        </div>
                    </li>
                    <?php endwhile; ?>
                    <?php endif; ?>
                </ul>
				<?php
                echo '<div class="pagination">';
                		if(function_exists('wp_pagenavi')) { wp_pagenavi(array('query' => $wp_query)); }
                		$wp_query = null; $wp_query = $temp;
                echo '</div>';
                wp_reset_query();
            ?>
                <div class="clearfix"></div>
            </div>

		</main><!-- #main -->
	</div><!-- #primary -->

<?php get_sidebar(); ?>
<?php get_footer(); ?>