how to build as non-root user

["ネルソンヘンリー" <nbsd4ever%gmail.com@localhost>]

Haven't used pkgsrc for many years.  Trying to get back into it, but
for the life of me
I can't get anything built as a non-root user.  In "the old days" I
remember building as
a non-privilleged user, and then being automatically prompted for
root's password for
the install.

Setting UNPRIVILEGED=yes in /etc/mk.conf doesn't change anything.  Building as
root works fine.  It looks a little as if I need to manually
chown/chmod at least the
"distfile" directory, and a "work" directory so the user building has
write permissions.
Do I need to do that for the whole /usr/pkgsrc directory resursively?
Or do I need to
download all the files as root before dropping into the unprivileged
user.  (How is just
downloading done?)

Help on the "pkgsrc way" to build as non-privileged user much appreciated.  TIA

-- 
hnelson