Travel Answers

Hello!
Id like to walk the famous gr20 track but I probably wont be able to spend 15 days for walking so I have to decide which part of it to take, northen or southen. I was thinking of walking the northen part from Calenzana to Vizzavona.
1. Has anyone taken it? How was it? Difficoulty in a scale from 1 to 10 where 1 is a walk on a beach and 10 is the hardest track one can imagine?
2. How many refuges were there? Can you camp on the track?
3. What about food? Is it best to take lyophilisated food or can you buy some food in small villages on the track
4. Im planning to go there in september, is it a good time?
5. How to get there the cheapest way? Plane/ferry/car/train? (excluding hitchhiking)
Thanks for your help! :)