I guess it depends on how big you want it to be. I live on the Isle of Man and a festival started up 3 years ago. The first year was quite small scale with a dance tent, main stage and small band tent, it also had a camp site. Last year it was alot better, i think in total there was 6 or 7 areas with other things happening like healing tents and well being etc. It was on for three days too.
I was talking to some of the organisers and they were in the 'red' still having not sold the festival out, they were saying that hopefully this year maybe next they will begin to make profits. I guess you have to start somewhere and have a plan and stick to it!