Doesn’t have to be, no, as long as he only has to set up a recurring transfer to a bank account and something buys ETFs and rebalances as needed.
The German banks aren’t a bad idea, but it gets more complicated as neither one of us speaks German (we’re Spanish). We could do pretty much the same thing with a Spanish bank, though, but I was hoping for something in Poland to reduce currency conversion fees and tax hassles.
Sure, IB is fine for us, but it’s not for everyone. The learning curve is pretty steep and you have to be really motivated to climb it. That’s not the case here, we need something totally frictionless or the money will just sit in the bank.