Angies List is a for profit business that attempts to give reports on good expereinces and bad experiences on business's around the US.

Angies List advertises that, companies do not pay to be listed on our service, consumers do.

BUT,

Nothing stops business owners from paying for the service and writing something positive about their own business..

How do consumers know that the person posting something positive about the business does not have financial gain from doing so?

If you want to do a more detailed background check on business, I reccomend going to the Better Business Bureau.