Anyone tried cloud radius servers

I’m doing a relatively small install in the coming weeks for a site that has no PC or server onsite to look after radius log-ins

there will be lots of wi-fi users > 100.
imagine a holiday home site and I thought the best way to look after all the authentication would be to use radius in conjuction with the AP controller in the balance 380
but I don’t know much about the cloud based services does anyone have any experience?

The site is looking to offer free wi-fi, a log-in per customer and some bandwidth limitations per month say 5Gb or so
just to discourage people from streaming movies. It would be nice if you could ask for payments should they go over the limitations

any ideas?