So I had to come up with a solution because my Teen Micah was almost ready to age into young adulthood and once he did I wanted to move in his YA girlfriend get them married and then move them out into their own home while still having my main family to play (his parents and siblings). But he is pretty skilled in most things and because the girlfriend was a NPC from the neighborhood she wouldn’t have the same rewards he did and would need nicer things to raise her needs quicker until she does get the rewards. So when I was ready to move out the Bride and Groom I went into my fridge and took out most of my fruits and veggies (especially the magnificent ones) and put them in his inventory and I also had him put some of his moms paintings (she’s a Gardner/painter/SAHM) in his inventory and some of the more rare fishes we had and I also put other things in the wife’s inventory (2 copies of each book) because my main family started very poor and it is very rich now so I bought books for them just to sell for a bigger house. I know this approach is harder and takes more time but it does work everything stays in your sims inventory when you move them. I’d say the worst part is that in the Sims 4 you can’t use the phone or computer to move out one or two sims you have to manage worlds and separate them from the rest of the family.