Hey all,

I need help with few English world. I'm writing the article about online services and I am stuck.

How to say in one world:
a) a person who post a job (like a person who write an advert on Freelancer.com) for example: I need a graphic designer or a babysitter etc
b) a person who offer the services for example: I am a cheap plumber and I can do ...
c) noun- an order for someone to do something and get paid like commission or errand.

Thx in advance