This is something I've been wondering about as I've noticed increasingly high stakes items being reviewed on sites like Yelp.

For example, I'm trying to figure out where I want to move next and it's commonplace for high rise apartment buildings to be on Yelp, but now that we're talking about a $25,000 lease rather than a $40 meal, the incentives to play around with the sentiment of the reviews are significant, as well as the potential financial reward for doing so. How can we trust the neutrality of the venue in these circumstances?