An apartment is definitely the way to stay in Paris. It was 50 euros in a taxi from the airport, but took all the hassle and stress out of public transport.
The apartment had everything we needed as a family and public transport links were cheap, on time and hassle free. Plenty of local amenities, bars, restaurants and patisseries. Lots of small supermarkets at reasonable prices, so it caters for every taste and wallet.
Highly recommend this stay, the apartment and its host were fantastic and we will definitely be going back!