Ugh, this is maddening. I had a Kafka-esque conversation with a Charles Schwab dude whose scripted answers almost comically changed when he learned that I lived in the Netherlands. It was fine at first, even with the understanding I lived abroad. But their deceptively advertized "expat services" only apply to Americans living in HK and UK.
It wasn't as bad when I called Vanguard, aside from the non-answers they kept giving me at first (they kept saying it was against US regulations and illegal, which I know to be false; when I pressed, they admitted it was purely their own company policy). At least she wasn't literally reading from a script and took the time to check with some supervisors.
When I called to change my address for an old work Fidelity IRA years back, the panic in the advisors voice, as he informed me I'd no longer be able to contribute to the fund, was kinda funny. Considering I'd never personally contributed to the account in the first place.
Interactive brokers are the only broker I've found to actually advertise as for expats, but the 10k min is a bit much for me.
Not the cheapest though, but I think they may actually be cheaper than my work place pension! I need to sit down and work it out.
I started with a £20 deposit, and just set up a monthly transfer.
Furthermore, good luck finding a place to invest in the first place. If looking for a US company, the likes of Vanguard and Charles Stanley will freeze your account if they find you reside outside the US. In the UK, I've gotten very used to seeing the text 'we are unable to open accounts for US, Cuban, Iran, Sudan, Syria, and North Korea persons'.
I make well below the standard deduction and just want to save a bit for my future. The US laws as they stand make this very difficult.