Cost
= flights+baggage+transfers+accommodation+food+ski/boot hire+lessons+ski pass
So basically it is a VERY wide address.
The cheapest option is usually booking yourself.
My sister is flying Kerry to Grenoble return for €40 all in
The transfer is €88 return by bus from airport to ski station.
Therefore car hire if you are in a group can be much cheaper...but with car hire you have petrol which is dearer in France and tolls...which can amount to €30 return per car.
We found Serre Chevalier in France excellent value last year....but really no apres ski much.
Self catering accommodations is usually booked by the week sat to sat...so you might be limited to hotels....some of which do have a kitchette type deal...which would cut down on food costs.....try and buy your groceries en route to ski stations as the regular supermarkets are much cheaper than the ski station ones.
Same for petrol 1 13 per litre v 1.43 per litre.
generally booking ski/boots on the net is cheaper than calling in and doing it in person.
If you are only going for a weekend private lessons can cost anything from €40 to €160 per hour. depending on resort and nationality of instructor....I find the englsih instructors charge more than the french.
With lots of research you should be able to get a good deal.