OnwardsandUpwards, when you fulfill this dream, first go to th country of your dreams and rent a house for a year and do not sell your UK home.
If after a year everything in the garden is lovely then sell your UK house and buy a house in the country you have moved to, but buy a small flat to keep as a pied-a-terre in the UK. You could rent it out.
I have noticed among people I know, who have retired abroad, that they get to an age, usually early 80s, when travelling to visit family in the UK is getting hardwork, or they have an emergency and help from home takes 5 days to arrive, when they begin to wish they lived closer to their family and a lot of them then want to move back to the UK, but that can take years to do in some cases because not every country has a house moving culture as fluid as ours, and things work a lot better if the person/couple still have a property, however small in the UK.
Even in the UK, a dear friend, decided to move from the South East to Yorkshire when she retired because she needed to release capital from her house and had worked there in her 30s and loved it.
We all advised her to rent for a year, because loving a place in the 1970s when you were in your 30s is not the same as trying to live there in your late 60s, 35 years later. We all recommended she rent for a year, but she refused to and went out and spent ever spare penny buying a house - and she found when she got to her Nirvana, that it had changed beyond recognition, - and she hated the place and found it difficult to make friends, but she could not afford to move back. She died a few years later before she was 70 and I am convinced her death was hastened by her disastrous move. If only she had rented first.