If you use standard gallery on your single property page e.g.
1. Please find: wp-content/themes/myhome/assets/js/sliders/gallery.js file
2. Backup the file for security reason
3. Edit the file
4. Find line below ( delay: 5500 ) - it is 5,5s
5. Change for any other number e.g. 1000 (1s)
6. Save
7. Visit your single property page and click CTRL + F5 to clear your browser cache to see new faster gallery