#!/bin/bash
HOST='yourserver.tld'
USER='backups'
PASS='ssh password'
TARGETUSER='local username'

cd "/home/${TARGETUSER}/backups"
RAW_OUTPUT=`ftp -n $HOST  <<END_SCRIPT
quote USER $USER
quote PASS $PASS
passive
ls
quit
END_SCRIPT`

FILE=`echo $RAW_OUTPUT | grep -oP 'backup_[0-9]{8}\.tar\.gz' | tail -n 1`

ftp -n $HOST &> /dev/null <<END_SCRIPT
quote USER $USER
quote PASS $PASS
passive
get $FILE
quit
END_SCRIPT

chmod u=rw,g=,o= "$FILE"
chown "${TARGETUSER}:users" "$FILE"