Best/cheapest thing are the Lane Shark mowers.
Pretty cool and affordable.
...if you don't count the price of glass? Or have good insurance?
How does that thing not throw chunks into the cab when tilted 90 degrees? Especially when taking out a hedgerow with 2" branches?
I wouldn't want an open cab either. Maybe a fine mesh screen? Or have the deck off to the side and closer to the operator station?
I like the suggestion of getting a sickle mower. Those aren't cheap either.
How far off to the side do you want to offset your 8' brush hog?