2x long connections - do we need a visa?

My partner and I have three stops in China and were wondering if we require it? We are hoping to explore both Beijing and Guangzhou, however if we are only allowed to leave one airport we would prefer Beijing.

We both hold New Zealand passports and our final destination is New Zealand.

Here is a copy of our planned itinerary:

Istanbul - Urumqi (6.15hr)
*1hr 5 min connection*
Urumqi - Beijing (3.55hr)
*17 hr 45 min connection*
Beijing - Guangzhou (3.35)
*22 hr 35 min connection*
Guangzhou - Auckland (11.30)

From previous answers I'm assuming we will need a Transit G? If so, how do we go about getting one? And is this useable for both long connections?

Thanks :)

Sapphire