And that's exactly when the handwave does come in... rather than trying to invent all the spells that were used to justify all the whackadoodle magical traps we find in all the adventures.
Maybe you have time to make all those up, but for me I just consider them all the "background magical effects" that exists in the world but which don't have specific rules (aka spells) for them in the book. I never want to have my imagination tied down to just those spells that WotC deemed worthy of including in the PHB... especially considering those are the spells that were specifically meant for adventurers' use.
If the PCs saw a magical trap somewhere and wanted to create it for their own home? DOWNTIME RULES, BABY! A couple weeks of study and experimentation, a pouch of cash, and then a wave of the hand... Boom! They now have that animated statue in their front hall... and I never had to adapt and make up a version of 3E's
Permanency spell at the barest minimum to do so. LOL!