Mickey,
I'm moving house too! If someone came to the house I'm selling and told me I had to do this and do that, I'd show them the door. In my experience, folks like that never come through when the moment comes for parting wit' brass. If they were serious buyers, they'd work out a deal with you.
On attics and a/c, I have a question about American homes. A friend of mine lived in Colorado, and his house did not have air conditioning as I understand it. Instead, he had to open the door to the attic, and then he started up this horrendous machine up there which had a big wheel on it and a 2" belt going around. I don't know what this was or how it worked, but it got some cooler air to the downstairs, so I guess it worked.