Hi I am traveling from nz with 3 in total traveling

The main problem with Shenzhen visa is in the fact that when obtained, you are allowed to stay and travel just within city administrative borders and Canton Fair is held in Guangzhou or, in other words, in completely different city.

My suggestion for you is to rely on 144 hours visa free transit in Guangdong province. So, take a look if something like this is suitable for your needs:
- Take a flight to Guangzhou
- Before taking a flight to Guangzhou buy a bus ticket from Guangzhou to Hong Kong. It has to be a through bus that runs from Guangzhou to Hong Kong and you should have this ticket (or ticket confirmation) with you in hard copy as a proof that you will be in transit in Guangdong province
- You really have to take this bus to Hong Kong
- Like this, your itinerary will be: NZ - Guangzhou - Hong Kong
- After you have entered Hong Kong, you can go wherever you want
- By doing this, you become eligible for 144 hours visa free transit that is valid for entire Guangdong province and you do not need any kind of visa.

Another option is that you buy a return ticket:

NZ - Hong Kong - NZ

After that, you will take a flight from HK to Guangzhou and exit to Macau by ferry from Shekou port in Shenzhen. After you reach Macau, you can return to Hong Kong and return to NZ from there. This is also valid for 144 hours visa free transit.

Is something similar possible for the Zhejiang province? (we have a return flight to AMS from HK)

Thijs, it definitely is...

Since you have a return ticket AMS - HK - AMS, you can enjoy 144 hours visa free transit by doing the following:

- Take a direct flight from Hong Kong to one of the airports located within Zheijang, Shanghai or Jiangsu provinces because they make one transit area.
- Take a direct flight to Macau from one of the airports located within Zheijang, Shanghai or Jiangsu provinces because they make one transit area.

If you do that, you will be eligible for 144 hours visa free transit in the wider Shanghai area consisting of Shanghai, Zheijiang and Jiangsu provinces.