wp_query

<?php

function get_cars() {


	$ne = $_REQUEST['northeast'];
    $sw = $_REQUEST['southwest'];

	$args = array(
		'post_type'     	=> 'car',
		'post_status'   	=> 'publish',
		'meta_query' => array(
			'relation' => 'AND',
			array(
				'key' => 'locationlat',
				'value' => array($sw[0], $ne[0]),
				'compare' => 'BETWEEN'
			),
			array(
				'key' => 'locationlng',
				'value' => array($sw[1], $ne[1]),
				'compare' => 'BETWEEN'
			),
		)
	);

	$query = new WP_Query($args);

	$cars_inside_bounds = [];
	$carIds = [];

	while ($query->have_posts()) {
		$query->the_post();

		$car_info = array(get_field(CAR::LOCATIONLAT), get_field(CAR::LOCATIONLNG)); //makes location string into lat and lng array

			$carImages = get_field(CAR::GALLERY);

			array_push($car_info, get_the_ID());
			array_push($car_info, get_permalink());
			array_push($car_info, get_field(CAR::MODEL));
			array_push($car_info, get_field(CAR::RENT_PERDAY));
			array_push($car_info, $carImages[0]['sizes']['large']);

	    array_push($cars_inside_bounds, $car_info);

	}

	print_r(json_encode($cars_inside_bounds));


	die();

}

add_action('wp_ajax_nopriv_get_cars', 'get_cars');
add_action('wp_ajax_get_cars', 'get_cars');