If you are wondering what places you should see in China and only want to come once….and insist on DIY. Here is my suggested itinerary route:
Beijing – 3-4 days
Xi’an – 3 days
Chengdu – 2 days
Zhangjiajie – 3 days
Shanghai – 2-3 days
– from Shanghai you can also see Suzhou (one day/day trip) and Hangzhou (3 days).
From Shanghai, I suggest heading to Hong Kong for a week, but that depends on your overall travel plans/time.
I would incorporate a day or two extra for traveling between these cities. As an example, between Xi’an and Beijing it is 6 hours by train.
There are of course a lot to see in China, it is a huge country, but these are the top highlights. From this, I’m quite satisfied that I have seen the country. But also from this, I realize I have spent way too much time meaning I have in total spent 9 days in Shanghai and a week in Beijing.
Of course, it was during Chinese New Years so there were other things to see.
Anyways, hope this helps.