Newbie & Air Con

Hi all, 

I'm a new member, first motor home and have just purchased a Windsor 2007. I was supposed to go to France yesterday but have postponed my trip for a month, hopefully it will cool down a bit as it's too hot for my dog.
I'm now considering having an air con unit fitted to the roof. Do any of you lovely people have any experience with fitting an air con unit to a Windsor (2007).     
Thanks
Clare.

Someone will come along better experienced than me, but on here over the years there's been a lot more articles re removing factory fitted roof air con and replacing with rooflights or electric fan rooflights.
Both still work off grid if you have solar....