## Clear out unwanted characters
$fstname =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$lstname =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$adda =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$addb =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$city =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$state =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$zip =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$email =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$phone =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$residence =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$yardtype =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$landlord =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$preadda =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$precity =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$prestate =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$prezip =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$alone =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$household =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$vet =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$pet =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$petname =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$currentpets =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$previouspets =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$references =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
$ok =~ s/[\|\/\\}{\[\]\(\)\*&\^%\$\#<>;:]/ /g;
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You have a lot of repetition that can be eliminated and using tr/// is more efficient than using s///g.

## Clear out unwanted characters
tr/|\/\\{}[]()<>*&^%$#;:/ / for
    $fstname,
    $lstname,
    $adda,
    $addb,
    $city,
    $state,
    $zip,
    $email,
    $phone,
    $residence,
    $yardtype,
    $landlord,
    $preadda,
    $precity,
    $prestate,
    $prezip,
    $alone,
    $household,
    $vet,
    $pet,
    $petname,
    $currentpets,
    $previouspets,
    $references,
    $ok;
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$email =~ tr/[A-Z]/[a-z]/;
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You are replacing all the '[' characters with the '[' character and all the ']' characters with the ']' character. That should be:

$email =~ tr/A-Z/a-z/;
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Or you could use the lc() function:

$email = lc $email;
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## Check email address
if (($email ne "") && ($email !~ m/[\w]+@[\w]+\.[\w]+/))
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You have needlessly included a character class inside a character class.

## Check email address
if ( $email ne ""  &&  $email !~ /\w+@\w+\.\w+/ )
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