Here is the email I got from Lochranza SYHA:
Every guest is upon arrival provided with a magnetic card which opens the door of his room. Only in case of stay in the dormintory other guests will have acces to the same room. Cards do expire at the time of guest's departure.
Our lockable bike shed can accomodate up to 15 bikes, but it can get easily full as the capacity of hostel is arround 50 guests. Then it is usualy possible to use our drying room as an overflow area, but this space cannot be locked. Alternatively you are welcommed to lock you bikes to our fence.
Bedding is included in any of the bookings. Private rooms (2 twin room of your booking) come with a free towel for each guest, guests staying in dormitory (6 males from you group) will either have to bring their own towels or hire them for £2 each.
Please also note, breakfast is not included in any of your bookings. We do serve continental breakfast between 8am-9am for an additional charge of £4,50. It need to be booked the night before.
Please remember that the earliest time for check-in is 5pm, when our receptions opens. In the meantime you are welcome to use our selfcatering kitchen and lounge equipped with additional lockers.
There is no cashmachine and no grocery store in Lochranza, please buy your own supply in Brodick or on mainland. Our reception has got limited selection of basic canned and frozen food, UHT milk and drinks and sells Arran bier (to the guests only) and Arran ice cream. There is also a pub (Lochranza Hotel), Sandwich Station, cafe at the distilery and Stag's Pavilion - family owned and often fully booked restaurant.
So basically bring a padlock if you want to lock stuff up, bring a bike lock and bring your own grub! Pretty much what we expected anyway.