We recommending using the PHRETS library by troydavisson, found for free on GitHub here: https://github.com/troydavisson/PHRETS

Sample.php

<?php

// Using "PHRETS" by troydavisson: https://github.com/troydavisson/PHRETS
require_once('vendor/autoload.php');


// Login to MLS IDX API
$config = new \PHRETS\Configuration;
$config->setLoginUrl('https://sample.mlsidxapi.com/Login.svc/Login')
	->setUsername('aQgXjDxarQcxFqqIrmfeTvuk')
	->setPassword('JNTHKsuoXySgTZZWJGZkipSP')
	->setHttpAuthenticationMethod('basic')
	->setRetsVersion('1.7.2');

$rets = new \PHRETS\Session($config);
$rets->Login();




function getSearchResultsArray($dbml, $limit = 100, $offset = 0, $format = 'STANDARD-XML') {
	global $rets;

	if ($offset) $results = $rets->Search('Property', 'Property', $dbml, [ 'Count' => 1, 'Format' => $format, 'Limit' => $limit, 'Offset' => $offset ]);
	else $results = $rets->Search('Property', 'Property', $dbml, [ 'Count' => 1, 'Format' => $format, 'Limit' => $limit ]);

	$parser = new \PHRETS\Parsers\XML;
	$xml = $parser->parse($rets->getLastResponse());

	// Convert to PHP array
	return json_decode(json_encode($xml, true), JSON_PRETTY_PRINT);
}


function addResultToDB($listing) {

	// Save results to your database
	//... 

}


function addAllResultsToDB($results) {
	$addedCount = 0;
	
	$propertyDetails = $results['RETS-RESPONSE']['PropertyDetails'];


	// NOTE: You must make your own "addResultToDB" function


	// Only one result, so force into array
	if (!$propertyDetails[0]) $addedCount += addResultToDB($propertyDetails);

	// Add a bunch at once
	else foreach($propertyDetails as $listing) $addedCount += addResultToDB($listing);

	return $addedCount;
}







// Search the last 5 hours
$dbml = "(LastUpdated=" . date('Y-m-d\TH:i:sP', strtotime('-5 Hours')) . ")";

// Set to Zulu time
$dbml = str_replace('+00:00', 'Z', $dbml);



$limit = 100;
$offset = 0;
$totalRecords = 0;
$totalRecordsAdded = 0;
$totalRecordsReturned = 0;


do {
	// Get results in simple PHP array
	$results = getSearchResultsArray($dbml, $limit, $offset);
	$totalRecords = $results['RETS-RESPONSE']['Pagination']['TotalRecords'];

	// Discontinue now if no records found
	if (!$totalRecords) break;

	// Save results to your database
	$totalRecordsAdded += addAllResultsToDB($results);
	$recordsReturned = $results['RETS-RESPONSE']['Pagination']['RecordsReturned'];
	$totalRecordsReturned += $recordsReturned;
	$offset = $results['RETS-RESPONSE']['Pagination']['Offset'] + $recordsReturned;
} while ($totalRecords > $totalRecordsAdded);