How to add the slider of images to single Property page.

If you want to add several property images to the single property page, you need first to disable featured image for each  Property item in Property Options -> Blog and single -> Single -> Show featured image before post. Please check the screenshot:

Then add Slider element using Visual Composer enabling "Custom slides" in Slider settings. It allows you to prepend slides and upload the image from the media gallery for each one.