It took me two tries. The first time I ran into a couple of roadblocks. My ISP wouldn't support it, so I tried a tunnel broker (since defunct). The tunnel broker wouldn't complete my application, despite several attempts to contact them. Then, I misconfigured something and assumed that my ISP was blocking the encapsulated traffic.
The second time around, I used a different tunnel broker and got everything running after a couple of days. After that, I reconfigured all my machines to make sure that they weren't using static IPv6 addresses when talking to the outside world. It turned out to be surprisingly easy in the end, although I would much prefer to own my own IPv6 block rather than relying on a tunnel broker, and I haven't fully figured out the best way to do native IPv6 address management in a segmented network.
It's crazy how ISPs and even otherwise-reputable hosting companies (ovh, blacknight) aren't taking IPv6 seriously. Get a free IPv6 address? You have got to be f- joking.