Here is a really useful website that will help you plan your accommodation for your visit to Aberdeenshire in September for the Etape Royale: Visit Abederdeenshire
Event camping facilities for all participants and spectators are available at a cost of £5 per pitch.
Camping is only available on Saturday 9th September 2017, in Ballater and can be booked when you register for the Event.
There is plenty of all kinds of accommodation available locally. Please see the Visit Aberdeenshire website or see below for Visit Ballater links.