Essentially you agree to a price per point with a DVC member. They will transfer the points into your account and the points become yours. This is usually easier than renting your points because you do not have to call MS to check availability, make the reservations, add the
DDP, etc. As soon as the points are transferred you are done - one easy phone call.
As for the receiving member, it is better to have the points in your account so you then can control the reservation and you do not have to go through the other member to make changes.
I just had a bunch of points transferred into my account for an 18 person 2 week trip. I found it much easier to manage all of the reservations myself - especially when some of the families changed their start/end dates for the vacation. If I had to go through separate members to change those reservations, it would have been a real pain.
Hope this helps.