This article from the NY Times travel section features useful tactics, some of which are already known to this forum's frequent participants.
One tip that was a new idea to me: Check a hotel's photos tagged on Instagram for a more realistic portrayal. These would be photos taken by guests rather than than the staged photos on the hotel's website.
Another tip often discussed here: Book hotels directly rather than through an aggregator service because:
Above all, though, booking hotels and flights directly means you are
only bound by one set of terms and conditions — meaning no additional
fees from a third-party site. And should you need to make changes to
your reservation, you won’t be jockeying for help from a middleman.