A arbeidsongeschiktheidsverzekering will cost around €4000 per year and they usually don't pay when you are sick. If you get cancer but can still sort mail, assemble key-chains or fill out an online inquiry chances are that they will not pay you. They will go through all your medical records to find any excuse not to pay you. You will have to sue them to get a payout. And you have to pay income tax on that.