Help are travel agent quit. Trying to plan a family trip 10 days Paris and London. This trip is dream trip, have stage 4 cancer given 6 months to live. We have raised about $10,000 for the trip. Travel agent told me she could have done it for about $8,000. Plan to leave June 23 or 24, stay in Paris until June 27 or 28. Than night train to England. Need hotel that can sleep 5, 2 adult, 3 kids 15, 10, 4. Kids don't need there own beds.
"in Paris .... Than night train to England." - there are no night trains between France and England. The only service is the Eurostar high speed trains which run by day and take 2½ hours. This is much too short a trip for a night train.
If you mean this June you need to book your train from Paris to London NOW. Go to www.eurostar.com. Some of the cheapest fares may already have sold out. The trip is two and a half hours, but only one and a half in clock time because of the one hour time zone difference. No need to go by night train, if you want to maximise your time in London on the first day just take an early train (but remember that you need to arrive around one hour before departure, as there are airport-style check-in, security, and passport checks).
It sounds like a wonderful thing to do with your family. My brother in law filled his wife's first year post-diagnosis with monthly excursions and experiences that have given his family wonderful memories.
Try and find apartments. I have used VRBO in both cites with success. Also Airbnb as i saw another Paris apartment at which I stayed listed there. I'll private message you the listing.
My 4 year old slept on the floor on an extra duvet. It was called "camping on a cloud".
Try Ibis hotels in Paris.