Me and t'uther half have just been looking into this and according to B&H Council it looks like a choice between Moulscoomb (6 courts - £6:10 at peak times/£2:80 off peak) and Stanley Deason (4 courts - £8 per at peak times/£6:50 off peak) presuming those prices are per person not per court, but not sure. Either that and do a 'Man of Harveys' and play over the telegraph wires in your street, although you may need to lob loads of pair of old trainers over them so that they sag down to meet the British Badminton Governing Body net height requirement.