@sculpt - Glad its giving you a challenge though as this thread mentions you should update to the latest 1.8.0.9!
The Hard AI does not receive any extra bonuses unless you add them in the settings (so no cheating for it). You can always review its past turns using the history feature to prove that it isn’t cheating (‘Game’ > ‘Show history’). If you are having trouble beating it then I suggest giving yourself a small bid to start with then decreasing that as you play against it more.
More details on the Hard AI and to follow its development you can go here: http://tripleadev.1671093.n2.nabble.com/AI-Development-Discussion-tp7585227.html