Need a StuDudley Guide or similar. Is there a good base?

to do what, when, how many people?

3 guys, eat seafood, drink and see castles and coastlines. need a good base.

You should search this site for trip reports that include Brittany for good ideas. Here's mine:
The Peabody Papers 2019, Paris and Brittany, Unmapped
We did well with 2 bases.

You can read Zebec’s current TR for ideas. He stayed in Quimper.

Or get the excellent Michelin Green guide book.

Cancale for oysters.

The Carnac alignments are a prehistorical site of thousands of monoliths that were placed in their position some 6,000 years ago. A must see. Excellent moules frites can be found in a casual unassuming spot in Carnac called Le Sinko.

With a week, I think St. Malo for 3 nights would be a good spot to base yourself to see Mont St Michel, visit St. Malo, Cancale, Dinan and then picking a spot further west for a few nights, like Quimper or Lannion, to explore the western half of Brittany. The rose coast of northern Brittany is gorgeous and worth a day exploring.

THanks. I have the green guide and sounds like a good plan! I will have a car, as it was actually pretty cheap...like 250 euro for the week, way cheaper than training 3 guys around lol