Do we need to run a campaign or can we hire these users without a campaign?
You can hire anyone for campaign even without having a campaign thread, it is based on your agreement with the person.
ChartBuddy = Seems like a bot and I haven't seen them post in any other board apart from WO were signature is disabled.
philipma1957 = Active user and wears signature
BADecker = Sees him mainly in Politics and Society.
JayJuanGee = Good poster and doesn't wear signature, you can try your luck
franky1 = Good poster with high knowledge of bitcoin, does wear paid signature but you can still try your luck.
Unless the user has a thread in which he offers his signature space, you risk getting banned if someone reports the PM:
I'm not sure anyone will report a user honestly offering to hire their signature. Atleast we are all humans here.