Wow, thank you for all the replies. This looks like a really friendly, welcoming site. I hadn't thought of working out the square feet. I make it 26 square feet sheltered and 36 square feet un-sheltered, giving a total of 62 square feet. I think their issue was the coop, and I can understand that if it was their sole accommodation.
However, events have overtaken us...
WE HAVE BUNNIES!!!!!
SSPCA rang up yesterday afternoon, so I picked the kids up, went in to town, and came home with two beautiful girls. All happened rather fast, and we've a bit freaked out!
They are 8 months old, and 'larger' ladies. The SSPCA rang us up as they knew we had the space for two larger, active bunnies. I think we'll try and make improvements to our set-up gradually, and let them lead us with what they need. It's going to be a steep learning curve.
After one night, we have loads of rabbit care questions, but unfortunately I work today, so I'll have to wait until lunch time to get some queries on here.
We're so excited and pleased. It's been such a long wait!