Hi
Although Kibri 26250 is a finished and ready to use model (probably a new strategy from Viessmann/Kibri), the Kibri models do not required any expertise or skill to be built.
I personally like to paint them before assembly, but it's not necessary.
The problem with Kibri models is the decal sheet.
I always produce my own decals, and I never use Kibri decals.
Thanks.
Regards,
Ayala Botto