Do I need Multisite? Community or BuddyPress?

Hi all,

I have a few questions that touch on more that one topic that I am having trouble finding answers to.

I am planning a Fundraising Community for medical expenses and special needs. I am currently using WPMU Fundraising for my daughters expenses and thus far have had no issue. Now that we are getting close to our goal I would like to use either BuddyPress (leaning toward BuddyPress) or Community coupled with Fundraising and open it up to the public as several of the people she has made friends with have asked if I could help in their efforts.

I have been trying to figure out if I even need Multisite for my project. From what I have found so far it is clear that if I want to provide individual "campaign beneficiaries" the ability to receive funds directly I need it. At first look that may not be a big deal, however I would like the process to be as simple as it can be. Maybe even wizard driven.

So, if my non-profit handles fund disbursements do I need Multisite to create what I am after?

Either way is there a means to streamline new member project creation so all they need to worry about is adding their cause, photos and if allowed their own info for payment gateway?

Hope this was not too long of a post. I just wanted to be clear about what I am trying to do.

Thanks for you attention in this.