If you can build up a trouble-free relationship with company people - that is, your bosses and colleagues - it will definitely be an advantage for your work.
First, you should cheerfully say Ohayô gozaimasu, meaning "Good morning". To your colleagues or your subordinates, it's not impolite to say just Ohayô without gozaimasu.
When you want to show your appreciation, you say O-tsukare sama deshita!
When you leave the office before someone else, you say O-saki ni shitsurei shimasu, meaning "I'm sorry to be leaving before you."
Go-kurô sama desu! meaning "Thanks for a job well done," is also an expression to show your appreciation, but it's only used by seniors addressing juniors, so you should never say it to your boss!
