I did a DD recently.
It took a number of preliminary phone calls.
6 international and 2 local flights.
A bit of car hire and a few motels.
Some nice dinners and drinks.
Meetings with some good people.
A 16 page report was presented at the end of the 26 days, 5 days before the deadline.
Low and behold, a major contract ensued.
Some just need more their time I guess!