The 8.7 had cash incentives, no additional points are in that price.
Quarter-end is approaching.....maybe this is a promotion to try and close business this month.
It's hard to recommend buying Trust Points (sorry to be the wet blanket). The $0.41 MFs approach the cash rental price for the reservation (from an owner -- not from Marriott) so you're paying the up-front for the right to make reservations. That's valuable, but is it $8.70 per point valuable? And as JimF pointed out, 2,500 points is just the start -- you'll need more in the future to really utilize the system. DVC does this, they sell you modest packages to start and are confident that you'll add more points in the future (and it works).
The good news is that you can rent points for $0.50 - $0.65 per point from other owners. If you do buy points, I would hope you would buy the smallest number of points possible and then rent what you need (until Marriott closes the points rental door -- or restricts it at least as Disney has done).
I may still be jaded from what I feel was some distinctly owner-unfriendly decisions that Marriott made -- and I just feel that this is the new pattern in the future. I would be reluctant to buy points in a system where I suspect its going to change in the future to my detriment. I don't mind modest changes or reasonable fees -- but fundamental usage changes are a concern.
One of the moderators here (Timeos2) is a huge believer that people should just rent the reservation they want from an existing owner (for not much more than the MFs) and not be sucked in to buying the week (or points) and being committed to the MFs. With Trust Points having such high MFs, I think that is doubly valid here. And I don't trust Marriott to be owner-first in the future. I'm very glad that I have my weeks -- and that I'm already in the DC system because it has value -- but I wouldn't buy Trust Points to join it.
Please let us know what you do -- and good luck to you, this is not a fun deliberation to have while on vacation (how is MOC looking??)
Thanks very much!
Greg