Free: Contests & Raffles.
Wait till January if you can. The new 2013 models will be coming out and there will be some great deals on the old models. Happens every year. There will probably be some great cameras for $50 to $60. (Which is all I have ever spent on any of the trail cams I own)
Really depends what you want out of the camera since some are better at one thing while not so good at other features. The battery life of trophy cam bushnells is what made me go that route. Not the fastest trigger speed so some pics are blurry but usually can make the pics out other than that has been a great cam. I paid $129 for the 8mp version. Have ran 3 trophy cams since June getting on average 500-1000 pics a week and still have not had to change any of the batteries. The batteries I am running cost me $3 at lowes for 30 no name batteries so I have spent $3 all year on batteries since June on my cameras. I have not tried any other of the newer cams other than these so cant talk to those but there is some great cams out there. I might pick one of the m-100 or m-60 up to try them out.
m80 is the cam to get. What ever you get. Make sure it takes AA batteries.