I've found that PREFIX alone is sometimes not enough. HTML::Mason, for example, would not install for me without all the added info. Here's the setup I use when I run perl Makefile.PL:
PREFIX=/home/tgi/usr/local \
INSTALLPRIVLIB=/home/tgi/usr/local/lib/perl5 \
INSTALLSCRIPT=/home/tgi/usr/local/bin \
INSTALLSITELIB=/home/tgi/usr/local/lib/perl5/site_perl \
INSTALLBIN=/usr/home/tgi/usr/local/bin \
INSTALLMAN1DIR=/home/tgi/usr/local/lib/perl5/man \
INSTALLMAN3DIR=/home/tgi/usr/local/lib/perl5/man/man3
I have this saved in a file called popt (for perl options) and I just issue the command perl Makefile.PL `cat ~/popt`. I like to recreate the /usr hierarchy of a traditional perl installation, but that is not necessary.
To add modules to your search path you have a couple of options. You may be able to modify the enviroment on your server through an .htaccess file (if you are on an apache based system). On a mod_perl enabled server, you can use PerlSetEnv PERL5LIB /path/to/private/libraries/. Otherwise you are likely to be stuck adding a use lib qw(/path/to/modules /ya/path/to/modules); to each script.
TGI says moo