Ok, in order to keep costs sensible I think it's going to need to be the bunkhouse option for all of us.
This place looks pretty good and booking the whole bunkhouse for 2 nights with current numbers works out at less than £40 per person. I thought two nights because we could assemble on the Friday evening and have a full day on Saturday and most of Sunday.
If you can take a look and let me know what you think. If everyone's ok with it I'll make some enquiries.