In reply to Elizabeth_S: there are loads of great routes in your range accessible from the descent gullies at either end of the crag. A 100m rope becomes more useful for subsequent visits when you are running out of the best routes closer to the gullies, and have a better familiarity with this massive crag so you know where you are going. A standard (60m?) ab rope is useful for the excellent single pitch routes on the Prow which is not so easy to access by scrambling. My top recommendations E2 Equinox. E3 Solango and Jolly Roger. E4 Face Value. Take lots of gear, two racks of cams. rockcentrics work brilliantly and a lot lighter than a second or third rack of cams. Also 3 sets of nuts, especially for Face Value. Wellington boots are very useful for the often boggy walk from car park to crag. Fairhead is more a North facing mountain crag by the sea than a sea cliff so extra warm clothes may be useful.
I live in Sheffield and have a 100m ab rope but would be very reluctant to lend it out, especially for use at Fairhead where the rough rock is likely to add lots of wear and tear.
Enjoy