If i'm not mistaken, there still is a requirement to file your tax forms to the IRS AFTER you have renounced your citizenship. I believe a stand down of 2 or 3 years. The rational behind the IRS is so citizens can not "frame" their exit plan by hiding assets and possible tax liability the IRS would be entitled to.The exit tax plan as well as just the whole tax plan of the USA is a nightmare. The increased cost to renounce your citizenship is just way to high. I don't care though, I will pay it, have to. It is way better than being strapped for a lifetime of tax to USA.
Overall, the IRS tax laws are not unique. There are a lot of developed nations that assess taxation on a whole wide world basis. Where the IRS stretches it's powers is it's strong bond to citizenship rather than just residency alone.
Perhaps a small cost compared to future taxes you will have to pay? No? As long as NZ has a tax treaty with the US, the only inconvenience is just filing. You will not be double taxed. Renouncing citizenship shouldn't be an issue of tax but rather an issue that where the country you reside does not allow you to hold citizenship elsewhere.So my family of our will pay $2450.00 x four to renounce our citizenship!