What are the words for: "One who try to sell his service by contacting people directly"?

What are the words for:

A man who searches for opportunities for his living (bread and coffee). He meet peoples at public places, and asks for a service (e.g: to shoe polish, to clean his/her vehicle, or sell something).

A man who contacts people by phone/email, and asks for a deal.

A man who contacts peoples at their home (door-to-door), and asks for & sells his service (e.g: for garden works, room cleaning, repairing, ...).

How can we call that person? Any words? nouns? suggestions please?

Thanks in advance.