I would like to take the overnight ferry from Nice to Corsica and Sardinia. Can anyone recommend a tour company or a guide or suggestions for doing it on your own. I am not sure the best places to stay on either island. I would probably be on my own and like to stay in a nice hotel with access to dining and shopping and perhaps get a private guide or a small group guide. I would like to go the end of May or beginning of June 2022.
https://www.corsica-ferries.co.uk/ provides the relevant ferry details and www.viamichelin.com has practical suggestions that used to be in the Michelin Green Guides to these islands (which seem to be out of print but an older edition might still be of interest). You probably don’t need to visit both islands as each is relatively large. A good, large-scale map is useful for driving.
I suggest the Public Library for Lonely Planet Italy and Lonely Planet France, as a start. Our cruise stops on those islands showed relatively little tourism infrastructure (other than beach resorts) and difficulty getting a taxi driver to book for a half-day or a full day - even through the TI. Not saying they aren't worth visiting. The further you are into the tourist season, the better, because of seasonal closures.