[efields]

Craigslist is an interesting comparison for friction/UX. Still looks like it's from the early 00's, but has stayed just usable enough on all contemporary devices that it never went out of style.

The only friction to the end-user is the same email/password request every other service makes, but you want to use CL because it's the de facto place for listing your apartment or whatever.

[vel0city]

I'm not sure if its true of every area, but in the cities where I've used craigslist it does not require a username or password to create or reply to a listing. It will confirm an email address when generating the listing. The link in the email contains the token allowing modification and deletion of the posting.