… and when I need a clean slate package wise:

#Delete packages and get rid of old stale libs:

/usr/bin/sudo /usr/sbin/pkg_delete /var/db/pkg/*

/usr/bin/sudo /bin/rm -rf /usr/local/*

#Recreate the directory hierarchy

/usr/bin/sudo /usr/sbin/mtree -qdef /etc/mtree/4.4BSD.dist -p / -u

#Install iwn firmware (if needed)

/usr/bin/sudo /usr/sbin/fw_update -v

#Add packages

/usr/bin/sudo /usr/sbin/pkg_add -iv [list of packages]