I had a nasty experience with the Dutch tax people. When we moved there, we took everything to the Tax office and asked if it was OK and was there any tax to pay in Holland. We were assured there was no income tax, so we left happy.
12 months later, we received a tax return, we thought nothing of it, filled it in, sent it back and the following week got a bill for 8 thousand guilders. He was right about no tax, but he hadn't told about all the other funds that Dutch people have to pay into. The actual income tax rate was 3%, the other 48% was made up of these funds.
We got an accountant to help us out and by the time we'd paid him he saved us a few hundred guilders. My advice - get an accountant for the first few years abroad.