You can write code on the page to check if the current user matches the one in the URL. If it doesn’t match, send the user to another page.
If that doesn’t meet your security concerns, then the way you first described will work as well. You can pass the ID of the property clicked using the wix-storage API and build the item page in the same way you describe the index page. Note that doing it this way means your users won’t have a unique URL for each of their items that they can bookmark, copy/paste, etc.
You also might want to look into doing this with router pages .