In my opinion, there is no need to get an agent, in fact for me, there is also no need to produce a contract agreement, just a verbal agreement will do. So long as you can see he/she is a decent person, follows your house rules, and is your friend, then there shouldn't be a problem.
But if you insist, I saw this in one website, http://smartpropertybuyer.blogspot.com/200...blog-links.html
Goodluck!