Here's my suggestion to improve UPDATING. I'd like something that helps
newbie -current users (like me) with DESTDIR. A similar update for
http://www.netbsd.org/Documentation/current/ should also be considered as it
doesn't discuss DESTDIR at all.

--- UPDATING.orig       Sun Mar 25 08:06:44 2001
+++ UPDATING    Sun Mar 25 08:12:23 2001
@@ -95,10 +95,29 @@
     Build to a DESTDIR:
        This helps to keep old
           installed files (especially libraries) from interfering
-          with the new build.
+          with the new build.
+
           To build to a DESTDIR, set the DESTDIR environment
           variable before running make build.  It should be set to
-          the pathname of an initially empty directory.
+          the pathname of an initially empty directory, such as
+
+          ~/current/
+
+               or
+
+           /usr/build/current/
+
+          or whatever takes your fancy. If building as a normal user,
+          the normal user should have adequate permissions for this
+          directory.
+
+          chown -R user <directory>
+          chmod -R u=rwX,go=rX <directory>
+
+          This allows non-root users to build the tree. It is also
+          suggested that you set DESTDIR in /etc/mk.conf if you are
+          regularly building -current.
+
           Problems: you might need to update critical utilities
                without using DESTDIR since nothing is executed
                from what is installed in DESTDIR.