In Netherlands, you don’t need to worry. All motorways are free of tolls. The only payments are for two tunnels: Westerschelde and Kil.
Tolls for passenger cars:
Westerscheldetunnel - 5 EUR
Kiltunnel - 2 EUR
Frequent users may have discount, but for this purpose, they need to have an on-board unit or special cards. If you go to Netherlands only for holiday, it is better to pay at tollgate by cash or credit card.
For more information you can visit the official websites of both tunnels where you can evaluate your possibilities.