Prinsjesdag 2019 is mainly about the Government's plans and the Budget 2020. In Chapter 1 of the State Budget ("The King") the following incomes are mentioned:
The King's personal income in 2020:
€ 949.000,-- (appr. US $ 1,050,000.--)
The King's reimbursement for his functional costs in 2020:
€ 4.940.000,-- (appr. US $ 5,462,000.--)
Queen Maxima's personal income in 2020:
€ 377.000,-- (appr. US $ 417,000.--)
Queen Maxima's reimbursement for her functional costs in 2020:
€ 643.000,-- (appr. US $ 711,000.--)
Princess Beatrix' personal income in 2020:
€ 537.000,-- (appr. US $ 594,000.--)
Princess Beatrix' reimbursement for her functional costs in 2020:
€ 600.000,-- (appr. US $ 664,000.--)
The Princess of Orange's personal income in 2021:
€ 282.000,-- (appr. US $ 312,000.--)
The Princess of Orange's reimbursement for her functional costs in 2021:
Yet to be calculated.
The total Budget in Chapter 1 ("The King") in 2020 is € 44.400.000,-- (appr. US $ 49,000,000.--). With all the indirect costs, accounted on other Budgets, the figure is roughly the double.
It is not clear if the Dutch monarchy is "the most expensive". One can also say: the most honest about all direct and indirect costs.