We contacted the Izitour, looking for a last minute private day trip for 2 in Ninh Binh and a few days later Mai Chau.
Communication on WhatsApp was smooth and easy.
The guided tours went well. The tour in Ninh Binh was maybe following super touristic spots too much and it felt that we could have found those on Google.
As for Mai Chau, very good day trekking in the mountains, stopping at a local's house in the middle of the forest for a break, this is definitely a tour where having a local guide is beneficial.
Speaking of, both guides were super friendly and spoke perfect French.
I would contact Izitour again for futur trips to Vietnam.