A simple script for downloading all images for a listing on BringATrailer.com

bat-download.js

(async function() {
  const delay = (ms) => new Promise(r => setTimeout(r, ms));

  // Given a url, try to download a high-res version of it
  // This prevents us from downloading a downscaled thumbnail
  function replaceUrlParam(url) {
    return url
      .split('?')[0] // get rid of querystring
      .replace('-scaled.', '.'); // Remove `-scaled` to attempt to get the full res image
  }

  // Open the full gallery. Wait a bit for the JS to execute.
  async function openFullGallery() {
    const showBtn = document.querySelector('.gallery > a > .show');
    if (!showBtn) return;
    showBtn.click();
    await delay(50);
    return openFullGallery();
  }

  // Open the full gallery. We try it a few times to be sure it takes
  await openFullGallery();

  // Get the full list of gallery image urls.
  const imageUrls = [...document.querySelectorAll('.gallery > a')]
          .map(a => replaceUrlParam(a.href));

  // Create an anchor link to virtually click.
  const a = document.createElement('a');
  a.download = '';
  // Now set each one to the downloadable image and download it.
  for(const url of imageUrls) {
      a.href = url;
      a.click();
      await delay(200);
  }      
  console.log('BaT image download complete!')
})().catch(console.error);

Good catch @handro123, fixed.