Types of small vans

Good morning from The Netherlands! I'm not a driver myself but I do work as a freight forwarder. I'm beginning to learn (as part of my training) about express transport i.e. small loads that have to be delivered ASAP from anywhere to anywhere in Europe. Also known as courier services.

I know there are some differences between vehicles here and there in the US but generally speaking could anyone give me a hint on the type of small vans/trucks that are normally used for express transport? As far as I know, the most widely-used here are basically as follows:

• 4.20 x 1.80 x 1.65, can take up to 1250kg --- narrower between the wheels (???)
• 4.00 x 2.00 x 2.00, 1100kg
• 6.00 x 2.40 x 2.45, 3000kg

Apparently for the 1250kg one there is a narrow gap between the wheels. Can anyone post a picture of such kind of van??? I work as a freight forwarder so unfortunately I don't actually see the trucks.

Thanks