Marks and Spencer have a promotion on at the moment, £7.50 for a towel bale containing:
2 face cloths, 2 hand towels and 2 bath towels
Face cloth: W30 x L30cm
Hand towel: W50 x L90cm
Bath towel: W70 x 120cm
Buy 2 for £12, plus if you buy 4 you get them for £24, the multibuy discount is made at the checkout you can use the free delivery code (attached).
So for £24 you can get 8 face cloths, 8 hand towels and 8 bath towels delivered. I think this is on in store, I certainly saw the £7.50 towel bale advertise when I was in there but not sure about the multibuy.