Also, be on the lookout for objects in the background that look foreign. For instance, the wall outlet in pics 8 and 11 look like type G, which are only found in the UK and some former colonies.
and I think it's a good sign if at least one of the pictures have them holding up the date or name or number or "LeoList", like many of the "verified" listings seem to include
that doesn't mean that it's a red flag without it, but pictures of women that look like they are from social media makes me think twice
and, of course, that won't guarantee ANY type of quality of service, but at least you know that the pictures are real!