public function modify_query_for_max_price( $query ) {
			// Do not mess with the query if it's not the main one and our CPT.
			if ( ! isset( $_GET['max_price'] )
				|| ! $query->is_main_query()
				|| INVP::POST_TYPE !== $query->get( 'post_type', '' )
			) {
				return;
			}

			// Get original meta query.
			$meta_query = $query->get( 'meta_query' );
			if ( ! is_array( $meta_query ) ) {
				$meta_query = array();
			}

			$meta_query['relation'] = 'AND';
			$meta_query             = self::maybe_add_meta_query(
				$meta_query,
				apply_filters( 'invp_prefix_meta_key', 'price' ),
				(int) $_GET['max_price'],
				'<=',
				'numeric'
			);
			$query->set( 'meta_query', $meta_query );
		}