Glosguy,
If these are weaners, then you could pick them up in the back of a hatchback in a dog crate or similar. Rules are that:
they must be contained - cardboard box not good unless very strong;
must be able to sit or stand at their choice - so room enough for your 4 or 6 if you are doing one journey;
adequately ventilated (again cardboard would need plenty of holes), wood box with decent size air holes would be fine, dog crate even better - just ensure they are getting lots of fresh air;
Must have straw to absorb wee and feaces;
I would also suggest that you put plastic under or the car will smell for sometime !
The container must be disinfected after the journey with approved disinfectant or burn't.
If you are travelling over 65km (from picking them up to delivery), then technically you would need to be qualified, but think you would be under this on these journeys.