[imp] Bastardized use of IMP/Courier IMAP as online file server ???

[Brian]

Consider the following theoretical scenario:
I run a club with about 100 members.  The members make payments to the club
and also occassionally receive payments.  Each member needs to receive a  
monthly statement of their account at the club; this statement must
remain private.
I don't want to send the statements out by snail mail and I also do not
want to send them out by email, say, because either not all members of the
club regularly access their email, some may not have email addresses or
I can't be bothered with trying to keep up to date with changes to their
email addresses.

Now, consider the following possible solution:
I set up a Courier IMAP server and each club member gets an email account.
Each month I email each individual club member his or her statement to their
address on my IMAP server under their address: member_name@mydomain.com. I also
set up horde and imp to provide web access to these accounts and supply each
club member with their password.
HOWEVER, I do not want the club users to think that I am essentially supplying
them with an email service. I would like them to think of it as a file server
where their monthly statements are stored and can be accessed online. I would
therefore remove all references to "Compose new message", address books,
delete messages and I would also restrict who could send email to these
club member accounts. I would also like to configure IMP, such that when
a user clicks on a message title to view it, IMP doesn't open the email, but
instead opens the first attachment to the email using the relevant mime driver
and the user gets to see a pdf version of their statement.
I also envisage using the folder structure of IMAP to supply each user with
other types of information related to the club and their membership.

My questions:
1. Surely, there a much simpler way to achieve the same effect - perhaps with a
completely different open source application?
2. If I do go ahead with an IMP / IMAP solution, do you have any tips on
things I should be aware of: possible pitfalls, shortcomings in the
solution, etc.?

Thanks in advance for your alternative suggestions or thoughts and opinions.
Regards
Brian