Paris hotel to CDG
 

staying in St Germain area in Paris , suggestions to get to the airport cab or train?

I'm looking for the same answer. I have been told the most inexpensive is to have your hotel set it up. By the way, what hotel are you staying in and what site did you find it on? Joy

Not true. Many hotels offer very expensive shuttle/private car services. It really depends on what you want to do. Do you want to deal with luggage on the RER but save quite a bit of euro? Or would you rather the convenience of a taxi but pay approximately 45 euro? It's a personal choice I find.

This is a perennial issue with decidedly divided opinions among Fodorites. Best way to summarize the options:
RER- cheap (under 9 euro per person) and don't have to worry about traffic, but you have to schlep your luggage and then get from the arrival station to your check-in counter, which may involve a walk or shuttle bus ride. It's what I use if solo or just one companion.
Cab - easiest for sure, risk is getting stuck in traffic, cost about 50 euro with tip if no excessive traffic delay
Shuttle (shared) cheaper than cab but you may spend a lot of time making the rounds of different hotels to pick up other passengers
Shuttle (private) - really just like a cab, cost can vary from about the same as a cab to much more for high-end vehicles

I am going the rer route seamus. Staying in Marais does that mean more than one major transtation dropoff. If you know off the top of your head.

If you are alone, the shuttle can be a dependable and door to door answer. If you are travelling very light, the RER is doable with a LOT of knowledge. The Marais will probably require two changes.
In either case if there are two people, then a taxi is almost as economical as the shuttle. Hotels will call a shuttle for you.

From the Marais, one would take the metro or bus to Chatelet les Halles for the RER.

For two of us, our hotel front desk arranged a taxi to get back to the airport from the Latin Quarter. It was not terribly expensive (~$50USD i don't remember exactly) and well worth the price for the convenience for us.

I guess it depends on the time that your flight leaves and how much work you want to do. Our hotel called the taxi for us. We had a morning flight out around 10 am or so, but I know we paid 60 euros. Everyone says that the RER very reasonable, but I wouldn't want to chance figuring it out with a morning flight. I guess the cab is a no-brainer if you don't mind spending the money.

Sarah -
The major objection most have to RER into town is having to deal with Chatelet Les Halles station which is enormous and confusing. There are other options, though, such as hopping a Metro at Gare du Nord. It depends on where your hotel is located. Many places bill themsleves as Marais properties if they are even remotely close. If you post the name/address of your hotel I'll be glad to see if I have anything in my notes.