台湾のタクシーは日本と比べるとめちゃくちゃ安いので気軽に乗れます。
桃園空港から台北市内まででも1000台湾ドルくらいなんで、4000円程度ですね。
市内移動だけだと400円くらいで移動できます。

Taiwan taxis are ungodly inexpensive compared to Japan, so we were able to board one without hesitation. It cost about TW$1000 to get from Taoyuan Airport to the heart of Taipei, which is about ¥4000.

For travel just within the city, you can get around for about ¥400. Airport to Taipei is about US$32.70 at current exchange rates, so intracity taxis are about US$3.30 per trip