Ideas
I did some testing with a fresh save with no CC or mods, after yesterday's update (in case it would've done something), regarding things people have mentioned here. For me, the problem seems to be the 50x50 lots in Mt. Komorebi (the Kiyomatsu Point and 2-5-1 Wakabamori) when my build is anything other than a residential or generic lot type. It being a recreation center, spa, bar, onsen.. all of them gave the error code. When I relocated the same build onto a lot in Willow Creek, there was no problem.
I also tested what someone suggested it being about crafting items and deleted everything from the lot that was a crafting item or a crafted item. So there were no easels or anything like that. Also just deleted some random objects to decrease the amount of objects in the lot. None of this helped.
Just simply relocating my lot somewhere else does not solve the issue for me because I spesifically built a winter resort... 🙃