I highly don't recommend feliway. While the stuff does work, the plug in often gets over heated and it can cause the container to break and the feliway liquid to go all over the place. I read that this happened to someone and their cat rolled in it and when the cat tried to lick the stuff off their fur before the owner knew what happened it ended up doing damage to the cat's tongue and throat. So very highly don't recommend that stuff.
As for your kitty that is peeing, it can be stressed. Even if you aren't packing yet, but are stressing about it, it can cause the cat to feel it and that can cause them to pee outside of the box. It can also be a UTI. So it may be necessary to have the vet check him for one. To help clean it up, I recommend getting a cleaner called Kids and Pets Odor and Stain Remover. If you follow the directions it works really well. It can be bought at Walmart stores. Here's a link so you know what it looks like.
https://www.walmart.com/ip/Kids-n-P...-Stain-And-Odor-Remover-27-05-Ounces/15724218