How to solve "Error #-200: HTTP Error when uploading property images"

The problem is not the Houzez theme, its possible that need setup the Maximum Images, Maximum File Size and Maximum Attachments, Maximum File Size for attachments in Theme Options >> Add new property

or perhaps need memory configuration on the php settings (not enough memory resources were allocated for the those kind of processes)

So you need to contact your hosting support and ask then to allocate memory.

Recommended PHP Configuration Limits

• max_execution_time 600
• memory_limit 128M
• post_max_size 48M
• upload_max_filesize 48M

More info about minimum theme requirements: https://favethemes.zendesk.com/hc/en-us/articles/360038085092-Requirements