! We live in a high rise apartment right now so building anything outside won't be happening til we move to a house and I will for sure hit you up for advice when that time comes!
I've never tried Feliway, have only tried the sprays that were cheaper than feliway. They worked for when we took them to the vet in their carriers (forest used to pee thru the door as soon as we put him in there lol). Does it matter if the plug isn't anywhere near the crate? We have 2 open plugs; one is behind a couch and the other is under the dining room table, both which are across the room.
I have heard you have to wait a month for it to start working, so I'd need 2 right off the bat and that might be expensive. What if I got a spray type and used it on his bed right after being out of the wash? Or would the plug-in be better?