add a sent box to a members online inbox

I have an online networking site: [login to view URL] it is quite a simple site and I want to add more functionality, initially to a members online mailbox 1) I need the icon next to a message in a members inbox to change to show if the message has been replied (currently it changes to show if it has been opened yet or not). There is a collumn in the database showing if the message has been replied to, so this should be very easy 2) I would also like to include a "sent items" for each member as well. Currently when a message is sent, only one copy is saved on the database. Hence when the recipient deletes the message it would no longer appear on the database. To create a sent items mail box there are two methods i can think of a) include an additional two collumns in the database for the message and rather than deleting the message simply change the input to a 0 or a 1 to show if it has been deleted of not, i.e. then on the inbox you would echo all message where "0" (i.e. not deleted) b) the other alternative would be duplicate the message being sent, i.e send two messages to the database, then when the recipient deletes thier version the sender will still have thier version sitting in thier sent box until they delete. There are lots of things in furture I would like to do to this site, I would really like to find someone who is good at php and styling and potentially available for furture work, plus any further improvements and ideas you could implement welcome :)