Save from what? Apparently he already has to use his savings to make ends meet. There is a myth that royals have golden apples falling from a tree. In the 1950's and 1960's the reigning (!) Queen Juliana of the Netherlands was in so narrow shoes financially with the official dotation that for years and years she had to dig the holes from her own personal wealth. With other words: the budget for the office of state was not sufficient so she had to pay from her private savings to fulfill a public office...
923.000 pre-taxation is really not that much. It will result in 550.000 netto. Imagine you have a cook, a gardener, a secretary, a butler and a chauffeur. Let us say these 5 cost 40.000 a year (employer costs). Most likely they have a few more staff. This is already 200.000 eating away. Let us say the energy and utility bills for the Château and Parc du Belvédère, the maintenance, the cars, the fuel, the insurance, the local taxes cost another 200.000. We are talking about someone who was heir for 40 years and King for 20 years. In comparison: Queen Fabiola got 1,5 million a year (free of taxes) . Reportedly 70% of this was used for the costs of staffing. The rest for living at the Château de Stuyvenberg.
So the single lady got a lot more (not taxed) than the couple Albert & Paola (taxed, because of changed legislation). And this while Prime Minister Di Rupo promised a settlement comparable to Fabiola (the PM's own words, in a rare break of confidentiality, on RTBf radio).