Depends on your comfort level....I do my own...I did 1st time thru an agent,,found out its the same amount of work,,,so now I enjoy the few $more per point for myself
If I am renting them out I have zero issue renting directly to someone. Just do it a ways out because you will have the money free and clear for months before someone is using your reservation.
If you are talking about renting points from someone else then I prefer this site but Facebook isn't terrible as long as you are careful.
There is a contract example floating around if you are renting your own points out. I would get something like that signed so you can have some clarity on what is and is not allowed and covered.