Weddingbee boards

For my sister in-laws last year I used these long low tupperwears I had (normal held my shoes- you know the kind that rolls under beds). They were the perfect height. Instead of newspaper (can get soggy and messy) I put empty water bottles and larger pop bottles between the arrangements and the side to buffer them from hitting. It worked really well and there was no movement at all. Then we just slide the tupperwears into the bed of a truck and we were good to go. Not sure if this would work for vases (hers were plastic pedestal type containers) but it might be worth a try. Good luck.

Cardboard wine cases. My FH is cutting them in half so our flowers can be transported without the risk of a spill

If you have access to a flower market, they have a TON of long cardboard boxes they can give you for free, some charge for the huge boxes but most will give them to you at no cost.

Once you have the long box, or tupperware bins, or whatever- you can either stuff them with newspaper and nestle the vase in. Or you can use a small box or a shoe boxes, flip it over and cut out a circle the size of the vase on the bottom the small box and place inside the big box with the circle facing up and insert your vase but make sure it's snug. If the small box within the big box doesn't fit right to the edge, stuff the sides with newspaper  so that they don't move around while transporting.

Or save the box that the vase came in and insert arrangements in those(stuff a little newspaper at the bottom so it will elevate the flowers over the top of the box.)

Make sure you only transport with enough water to touch about an inch of your stems and then refill once they get to the venue.

Hope you can understandmy long attempt at instructions, if not, send me a PM and I'll send you a picture. I transport a lot of arrangements and this is what I do :)

good luck!