I was hoping someone could offer advice as to the best way to get to the Marriott London County Hall from London Heathrow. I will be traveling midweek with 2 children - ages 10 and 12. I see posts about using the tube, but not sure about transporting all our luggage and keeping track of it during transit. Last time I was in London it was years ago and found the tube pretty easy to get around. This time, with kids, I was thinking a taxi or London Heathrow Express? Also, any advice on getting a travel card or Oyster card?? Any advice on tours to take? Should I go with a tour company, do the hop on hop off bus. If anyone has stayed at this hotel before, will they accommodate for upgrades - I am platinum status. Thanks for all your help!!