My preference would be Honfleur or Trouville. The former is very pretty with a huge selection of places to eat. The latter more 'workaday' (and hence sensibly priced). Deauville itself is pretty pricey but good restaurants take some finding.
Two weeks ago there was no Avgas at Deauville - it was 'broken' but not notammed - so if you are set on Deauville I would suggest phoning them. The nearest fuel was at Le Havre which is only a short hop - but you then need to fax a flight plan from there - so add another hour on.
If you choose Honfleur then Le Havre is pretty much the same distance in a taxi but over the bridge. Deauville control the class D and then turn you over to Le Havre.