vehicles inAreaArray myTrigger;
allUnits inAreaArray "myMarker";

from https://community.bistudio.com/wiki/inAreaArray

these are quite expensive if you have 30+ vehicles or 200+ units

https://community.bistudio.com/wiki/nearEntities is the most efficient (AFAIK)

possible to extend it with [typesExclude, includeCrews, excludeDead] optional parameters from https://community.bistudio.com/wiki/entities to make it even more efficient?

also helpful would be such filters for vehicles and allUnits

As suggested by Killzone Kid to the request above