He just asked for an item to replace it and I gave him a modern sofa in a haste thinking he'd give me the Sloppy sofa (Gave me Regal Vanity instead) so did I just screw myself over? If he invites me to his house later now it's not going to be there and I won't be able to buy it off him, right? Or is it going to show up in Re-Tail soon?
In my experience, whenever I clear something out of a neighbour's house, they usually give it to me for free/try selling it to me later.
If you do the swimming glitch to activate a conversation with them, that might work too.
How do you do the swimming glitch? Just go swimming and then come back? I have never heard of this glitch so..
I hate how people call it a glitch, it's not. The ocean tends to be the furthest thing away from the neighbors and that combined with a few minutes means they'll get the "!!!" reaction when they see you.
Just swim in the ocean for a few minutes, dive for some goodies and walk in from of the animals to try to get a reaction. Also, animals have an inventory. Ankha had her throne in her pickets for 3 days before she gave it to me.
One thing that I noticed on my game (not sure if this happens for anyone else), is that if you catch the neighbor in their house when you bring them something to replace the furniture in question, they will usually give the old item to you. Have you tried that?