Cert of residency

Does everyone usually prepare this when they go teaching in Korea? Apparently it says in the contract you get tax deducted if you bring a certificate of residency (from abroad) with you.

Is the amount saved really that big a difference?

While Korea is a low tax country, it is not a no tax country, it all adds up. I don't know how much tax I pay as it is all handled by the administration office.
 
If you can get this, get this as this will reduce your tax.
 
Sadly I can not get one of these as I was not living in NZ long enough before I went to Korea.  :(

While Korea is a low tax country, it is not a no tax country, it all adds up. I don't know how much tax I pay as it is all handled by the administration office.

Yeah, get it if you can. I would say the tax (on a regular EPIK job), is not huge each time, but it adds up. Plus, if you are a US citizen, you won't have to pay any taxes there (up to 80,000 USD) or here. That will help you save even more money!--if that's why you're here :)