Orange, Sainsburys in FH has 'all that space at the back' because it is the only free car park in the area (for 2 hours.) I suspect that none of the local traders would be thrilled to find it closed for a day. I think Andy is right that the best site is at the rear of the Dartmouth. I remember the farmers market that was held there a few years ago and agree that it could be more successful now.