Wow AutoGids, you have cleaned up, with more points in one day than the last month combined! Good work.
So, in summary;
#1: Estancona (1953): Inspired by - Morris Minor
#2: Hoffman: Inspired by - ISO/BMW Isetta (and successfully sued by BMW), but with a side-opening door
#3: FH Camioneta: Inspired by -Citroen 2CV Fourgonette
#4: KAPI M190: Inspired by - Mercedes-Benz 190 SL
#5: Orix S.F. (1954): Inspired by - VW Type 1 (Beetle, Kafer, Kever, etc.)
All cars Spanish, excluding the German Hoffman, making this (#2) is the odd one out
So, for a final point, we now know that all of these cars were inspired by better-known contemporary vehicles, but what other thing unites them all?