I've been working remotely as a freelancer since 2020. As I travel around Latin America in parallel with work, one of my biggest challenges is finding a stable internet connection. In some places, it's non-existent or not strong enough to take calls. So I couldn't visit some towns because of that.
In terms of payment, all my clients are coming through Upwork so the payment is released automatically on a weekly basis. I used to miss a personal connection and working with a team from somewhere but got used to a remote environment after a while :)