Alan, you have a wonderful set of travel plans.
The site you mentioned "Self Catering", have you used it before? I looked at a few rentals and they looked quite reasonable. There did not appear to be posted renter comments but maybe some selected snippets. How does one do the due diligence on this sort of rental? Any suggestions?
When you select a place to stay for a week, do you have in mind a village nearby and several attractions that lure you to that exact local? Maybe this is a dumb question but sometimes I struggle with whether we'd be happy in a quite setting for a full week. In the UK for instance, selecting a good location outside of maybe London is challenging for us. We have been in areas for a week with great hiking trails like Mammoth Lakes California (near east Yosemite entrance) so are not total newbies on this stuff.