Ask HN: Get paid to interview/vet candidates

I have a company and trying to interview candidates (Graphic designer role and a sales role) who have been referred to me but these are new roles for our company (no one knows what to ask)? Is there a place I can pay professional people to vet my personal candidates?

Also I have looked into Recruitment agencies but they give me a list of candidates through their own filter that I do not like and they generally cost way too much.