If I were a betting man I'd bet that the electrician/plumber/hvac lobbies will get their respective fixtures locked down (in a similar way to a lot of automotive stuff is currently) so you need to pay someone with a license to use them before we get microtransactions in vehicles.

As much as all these industries would love to make pennies here and there, they all loathe the idea that people can do things without giving them a cut even more.