Next Tuesday I have a small farm that needs to be brush cut. I'm renting a walk behind brush cutter from an equipment company for $60 a day (a snapper 42 ' cut, or I could go with a billy goat 42' for an extra $10). I've never used these machines. For light brush do you think I will be able to mow acre an hour? What about gas? Do they consume massive amounts of gas per hour? Finally, any tips for things to keep in mind while operating the machine?