use HBCI;
my $konto_1 = new HBCI::BankAccount($BLZ, $KTO, $PIN);
my @buchungen = $konto_1->getTransactions([$fromDate[, $toDate]]); # HBCI::Transaction
my $guthaben = $konto_1->getBalance();

for my $t (@buchungen) {
    print "Buchungsdatum: " . $t->getDate() . "\n";
}

...