Log Retrieval Script
handle more possibilities

Anything touching the file system can fail.


mkdir You could have permission problems or something else.  Do mkdir foo || exit 3.  Feel free to replace the exit with your own function for error handling.
cd is the same deal as mkdir
check for the existance of your directory before lsing it: if [[ -d $PlaceLogs ]]


Also, do any bz2 exist after the sftp?  You should check before bunzip'ing them.

You can safely ignore all of these things too, but since you specifically asked about error handling it seemed good to point them out.  If this is a critical piece of software then I would build a way for these failures to raise alerts with your DevOps team.

shellcheck.net

Run all of your scripts through http://www.shellcheck.net/ until you get in better habits.

use double square brackets

Double square brackets are better than single square brackets.  They have less surprises.  The primary one is that if you have an empty variable you can do

if [[ $FOO == "" ]]


where single brackets require a placeholder so none of the arguments disappear if missing:

if [ x$FOO == "x" ]


Without the xs the $FOO would disappear as a shell argument when empty.