The line of ROCO Minitanks has lots of excellent military vehicles - but you can use a lot of them for civil and peaceful purposes, too. There are open and closed trucks, dump trucks, pick-ups, jeeps, fire-fighting vehicles, bulldozers etc. etc. There are even accessories like tents, Nissen huts...
They could also be converted and kit-bashed quite easily. Look at
this site under 'Minitanks' for the whole collection!
Ron