Getting an item by calling GetItem in the Trading API using the [eBay SDK for PHP](https://github.com/davidtsadler/ebay-sdk-php)

trading_get_item.php

<?php
require __DIR__.'/vendor/autoload.php';

use \DTS\eBaySDK\Constants;
use \DTS\eBaySDK\Trading\Services;
use \DTS\eBaySDK\Trading\Types;
use \DTS\eBaySDK\Trading\Enums;

$service = new Services\TradingService([
    'authToken'   => 'your-auth-token',
    'credentials' => [
       'appId'  => 'your-app-id',
       'certId' => 'your-cert-id',
       'devId'  => 'your-dev-id'        
    ],
    'siteId'      => Constants\SiteIds::GB
]);

$request = new Types\GetItemRequestType() ;
$request->ItemID = 'your-item-id';
$request->DetailLevel = ['ReturnAll'];

$response = $service->getItem($request);

if (isset($response->Errors)) {
    foreach ($response->Errors as $error) {
        printf(
            "%s: %s\n%s\n\n",
            $error->SeverityCode === Enums\SeverityCodeType::C_ERROR ? 'Error' : 'Warning',
            $error->ShortMessage,
            $error->LongMessage
        );
    }
}

if ($response->Ack !== 'Failure') {
    $item = $response->Item;

    printf(
        "%s\n%s\n%s\n%s\n%s\n(%s)%.2f\n",
        $item->ListingDetails->ViewItemURL,
        $item->ItemID,
        $item->Title,
        $item->Description,
        $item->Quantity,
        $item->SellingStatus->CurrentPrice->currencyID,
        $item->SellingStatus->CurrentPrice->value
    );

    print("Domestic Shipping Information\n");
    foreach ($item->ShippingDetails->ShippingServiceOptions as $shipping) {
        printf(
            "[%s] (%s)%.2f\n",
            $shipping->ShippingService,
            $shipping->ShippingServiceCost->currencyID,
            $shipping->ShippingServiceCost->value
        );
    }
}

vendor autload php did not fined on your sdk