Despite that the point of roleplay is to mimic real life, not all job titles are allowed. They are mostly a variation of citizen, but can be variations of other jobs. The reason for this is that most banned job titles incite rule breaking, or make the game unfair.

Real Estate Agent[]
On lots of servers there is a job were you can buy doors and sell them for a profit. You cannot do this on this server. You may own as many doors as you wish but you must use them all.
Hitman[]
On lots of servers there is a job were you get hired to assassinate (kill) someone. This is not allowed and counts under the rule of RDM
Killer/Crazed Gunman/Shooter ect.[]
These jobs have a tendency to be either banned or unregulated from most servers. The reason for this is that is incites RDM and causes chaos.
You will not get a punishment for any of these but you will be told that the job is not allowed and that you need to stop and change your job.