I think
DVC is more likely to ROFR a small contract for a new member. Their costs to service that member with a low number of points is the same as a member with a large number of points. They would rather have a member with 150 points than 3 members with 50.
As far as I know, DVC can do it. The contracts are percentages of a unit. So if someone is selling 5% of unit 44B, they can break it up into 5 contracts of 1%. The unit itself is the same.