In reply to Cjkelly83:
If your an Mountaineering Scotland member - have a look at their club huts directory as a lot can be booked as individual members. The Smiddy in Dundonnell would suit your group well for example as would Naismith or Ling huts.
Ceildhi place has a bunk house in Ullapool, but no kitchen facilities unfortunately.
Torridon youth hostel is to be recommended, and will normally allow you to book a dorm room for your group.
Caving hut in Elphin - also very good.
There are cabins you can rent near to Reiff (possibly via An Fuaran pub?) also which are well situated.
Unfortunately most of my trips are via climbing club (Aberdeen MC incidentally) or camping / camper vanning so not much personal experience of other bunkhouses.
Cheers,
Stu