In your Real Estate software, you can choose to set a default thumbnail size for your Property Listings.

To change the default listing thumbnail size in the Real Estate software

1. Go to the Real Estate Settings tab when you are logged into your Website account.
2. Click on the Details tab.
3. Under the General Details heading, choose width in pixels that you want you thumbnails to be in the Listing Thumbnail Size field. 
4. Click Save.