What are the good indicators of fake conferences?

In your description, there are three telltale signs that the conference might not be very good:

1. The reviewer email is revealed: a conference that doesn't protect reviewer anonymity (blind review at least) is probably not very good.
2. The review itself is, frankly, not high quality. It may make sense for a standard conference scientific committee to appoint another reviewer if the first one didn't do his job properly.
3. Financial details appear very important to the organizer…

To make your final decision, see answers to this question: check out the organizers and invited speakers.

Seek the opinion of third parties. Here are some suggestions.

• See if the conference is indexed by a major digital library, like Scopus.
• See if the conference is sponsored by a reputable professional organization, like the IEEE Computer Society or the ACM. Although these societies sponsor all types of conferences, from top-rank to less illustrious ones, I haven't heard them sponsoring "fake" ones.
• Have a look at the Conference Ranking Exercise that has been performed by the Computing Research and Education Association of Australasia (CORE). If the conference is there, you'll get a (subjective) rank of its importance as a publication outlet. Note that the list is somewhat dated.
• Similarly, look at the conference ranking list compiled by Osmar R. Zaïane at the University of Alberta
• Consult the automatically-compiled list created by Microsoft's Academic Search engine.

An alternative approach that a group of researchers followed back in 1995 is to submit silly or gibberish papers (e.g. "The Footprint Function for the Realistic Texturing of Public Room Walls", "Visualization and Intelligent Design in Engineering and Architecture ", "Distributed Multiprogramming System for Pen Selectors with Error Probability") and see whether they get accepted.

I have many years of academic experience and I have been a reviewer of submissions for conference presentations and scientific journals. Speaking from experience, often times the reviews given in response to a conference abstract submission can be extremely brief. This is often due to the reviewer having way more submissions to review than they ever dreamed of and a deadline of say "tomorrow" - YIKES! Serious though... Okay so moving past that, to judge the merit of a conference, I would make most of my decision based on the conference hosts or sponsoring group. If they have a large or influential membership within the discipline, who is directing the group of conference and their professional reputation, the size of the conference venue, etc... if that is all positive then I would go for it.

You might call up a colleague or two of yours in academia within your discipline and ask them if they would like to attend the conference with you. Sometimes those that are currently in the academia loop have insight about the "perceived impact" of a conference or sponsoring group.