I've been looking on the net for one, and for around £250 you can get a decent one which comes with the window kit.
We have literally done nothing, and getting the dog out for a walk is turning into going out either very late at night or very early in the morning. Sleep has been at a premium.
Must admit, cooler nights will be welcomed, but Don't want to wish away this weather, as it won't be long before the endless days of grey skies and wet and windy days take hold through autumn and winter.