If you really want to camp on the cheap, there are several primitive camping areas in the National Forest, in Evans Notch (called, Basin, Cold River, Wild River are campgrounds, then along the trails there are more really primitive sites) , just south of Sunday River, that are either really cheap or free, but they are usually first come first served. Although I think some of the areas allow reservations online. Keep in mind that this is Labor Day Weekend - a big camping weekend up here, so chances of finding openings are pretty slim this late in the game. The first come first served ones usually fill up by about 10 AM Friday morning before long holiday weekends. Unless its raining, then you'll probably be in luck. Note that on the website it says that Hasting trailhead is closed while they replace a bridge that got washed out. Here's the site: http://www.forestcamping.com/dow/eastern/wm.htmAre there any additional camping suggestions?