Funding the kids toy stash at your ex's house

One of the turning points in my ex and I stabilizing the situation with our kids after we separated and then divorced was for us to agree that things we bought the kids were their property and that they could take them from one house to the other without us intervening.

It's a recommended philosophy in co-parenting (e.g., parenting after a divorce) books too and saves the kids lots of stress about "toys at mommy's house" and "toys at daddy's house" and it also just makes intuitive sense.

I know that if I were a child of divorce and I got into a new toy or game, I'd want it to migrate with me, not be shackled to a specific building, address or parent. Ideally, it'd all just work so smoothly and my parents be sufficiently close geographically that I'd never even really think about it.

But from a parent's view, from the view of the person who certainly seems to buys the majority of these things, well, it doesn't always work out as desired...

Here's the problem: if one parent (me) is more likely to take the kids shopping or buy stuff for them while we're out, then it seems inevitable that eventually things I buy migrate to the other house far more frequently than they come in the other direction.

Given enough time, the situation could end up where I'm stocking the toys for the other parent's household, even while child support is supposed to be the mechanism in place to balance out money so that each household can afford what the kids need.

Now let me add another wrinkle: what if we were talking about clothes, not toys? Expensive shoes, nice jackets, jeans, skirts, and even mundane things like socks. Fortunately, Linda and I have figured this part out and occasionally "resync" clothes as she often seems to have lots of the clothes I buy the kids, but we never try to resync toys, sporting goods, or similar.

This week A-, my 13yo, really wanted me to buy a nice volleyball, which I did without complaint: she's on the school volleyball team after all and is also a very good player with a potential sports scholarship in her future. She explained to me "we don't have a volleyball at your house, Daddy" and I agreed. Problem solved.

Until I went to drop her off at her mom's place and she insisted that she take the volleyball with her and not only keep it there, but take it with her when they subsequently go on a multi-week holiday with Mom to a family summer house.

Been here, done this before, and I had no doubts that it would be the demise of the volleyball. To say "yes, you can take it" was to say adieu to a pretty nice $30 ball.

So I said "no". Instead I said "the ball was bought to live at my place. I'll leave it in the garage. If you need a volleyball to take on your trip, ask Mommy to get one."

With a bit of a huff, she grudgingly consented.

Still, what bothers me about the situation is that it made no sense for me to buy things for my kids to just take to their Mom's house, and yet that's exactly what I have tried to do anyway, let the things I buy my kids become their property, for them to do with as they see fit.

Does that mean I should stop worrying about things, stop keeping track of the stuff I buy my kids (esp with a teen girl just getting into fashion) and just let things migrate where they will? Or is there some sort of middle ground where before things are purchased, they are denoted as "portable" or "stationary"?

If you're divorced, dear reader, or from a divorced home, how do you suggest I should have handled the volleyball situation?

ps: after some thought, I texted my daughter that if Mommy wouldn't buy a new volleyball for her, I'd buy her another one for her to take on vacation with her. She hasn't responded...