Caburé is not even a village in Maranhão. Beautifully situated between the river and the sea, sometimes covered in a fine layer of sand carried in by certain winds. Its proximity to Lençóis Maranhenses could make it a base camp, but there is the river in between. Go for Atins instead.
No scheduled transport.
As an alternative they also offer transport by 4x4 cars, which will get you there for about R$1000 for a car. It will get you directly to Cabure - with a stop in Parnaiba (to eat and get money - no banks in Atins!). To make this form of transport affordable for most travelers, they combine groups of people in the cars. See their site for more info:globalconnection.tur.br
So small, so small
Each pousada has its restaurant, -all quite expensive (around R$ 30 a dish). If you approach before or after the daytrippers, you could be able to negotiate a cheaper set lunch.
Four pusadas in a row. Singles ranging from R$ 40 to 100. Negotiable in low season.