if you can afford it, pay for a driver for a few days, and have them stay in a nice foreign hotel (often not too pricey) - getting a personal English-speaking guide can also be a great experience if you get lucky.
the driver idea worked out really well for me in Chengdu - everything becomes more convenient. In Beijing we got them a guide who was totally charming and really made the trip for my folks (it was their first time). In Xi'an the guide was awful. Luck of the draw to an extent, but interviewing them in advance helps.
The guide is if you're working and can't be with them everyday. The Driver is if you have time to be the guide yourself.