It is an honour for them to have tourists in their houses. There are certain 'risks' though. This covers transport, lodgings and meals for the entire duration of the stay, which is usually 2 days 1 night. The package comes with an English speaking guide acting as translator as well, as most villagers know little or no English. The trip from Hanoi to Mai Chau takes about 5 hours on mini buses or coaches.
Tourists can book the package from tour agents or from hotels in Hanoi.
It is not advisable to make the journey on your own as the country roads are bumpy and not well defined. There is also the language barrier to deal with. Print them into hard copy versions with Photoprints.