Ive ten years experience visiting the following: Chamonix – Le Tour, Argentiere, Les Brevieres, Les Houches, Vallorcine, Mont Troc, Finhaut, Martigny, St Gervais, Megeve, Les Arcs/La Plagne, Villar Roger, Les Gets and Flaine.
Get a Pierre et Vacances, or private chalet. Chamonix or Bourg Saint Maurice are excellent bases.
Tape up your frame to protect the finish – cable cars get rammed with bikes and this is when your expensive bike will get ruined..
Take plenty of spares as things will break and local bike shops really mug you, not to mention the lost time out for repairs.
Respect the dangers of the mountain, make sure you are adequately insured and go carefully – helicopters are expensive (as my mate discovered).
Find out which lifts are running and which days, before you plan an itinerary.
Pay me to guide you for a week! 😉