Hello

Congratulations on early retirement:

I would suggest that you get the highest output solar panel that will fit your MH. Personally we prefer to drive through France, the Bay of Biscay can get pretty rough and we enjoy the driving. Spain can be cold especially through the North and over the central plains, so take some thick jumpers and warm bedding!

Spinner

I haven't done the trip myself, however when I thought about it before, I think I estimated that taking the ferry to Spain cost double what it would to drive through France. France is lovely and I would drive it myself.

As for the solar panel, I wont bang on with my opinion again, however if you don't plan to stay in one place for more than, say, 4 days, you wont need one.
However if you plan to stay put for a week or two in one place, I agree with Spinner get the highest output one you can and make sure it is a full kit with the controller etc. You can buy them as portable suitcase types or have a fixed one fitted to the roof.
As for a bargain at the show, you will be very lucky.

I met a guy this weekend who has 400w on his motorhome roof and claimed it wasn't enough as he works off his laptop daily so he was adding 2 more panels to make it 800w! A bit excessive maybe but all depends on your power usage.