Staggered at your quote SW18er!
I've just had mine done (terraced single fronted house), the total cost for the cleaning was £1025, which included the scaffolding, and they repointed the apex for £300. No damage was caused by the cleaning (I had a quote from another party who said all the pointing would fall out with the cleaning- which it didn't
My repointing doesn't necessarily need redoing, except that it is dark grey/black, and doesn't look very nice. So they have quoted me £2000, which I'll probably do next year now. The chaps who did mine are a father/son team- Alan Lamb on 07956 271008. Very nice, and obviously reasonable!