If you are going to get a decent full suspension bike, you are doomed to pass the $1000 mark. If you want decent disk brakes, you will have to spend over $500. Disk brakes differ from rim brakes in stopping power and durability. one Major advantage with disk brakes is that once they wear down, you don't have to replace the whole wheel. You don't need disk brakes if you aren't going to be doing real racing. If you are just going to stick to gravel trails and double track, just stick to something under $400, and get your bike from a real bike shop, not walmart or target.