Cost splitting calculator

There are apps out there, for this, but once again, I haven't seen any that include all the features to be truly useful. My ideal cost sharing app would allow an unlimited list of people to share an unlimited list of costs. The list of participants would be exportable. The list of costs would be exportable. Attaching date/time to each coat would be an option. Each person's participation in any single cost would be optional. People would be able to pay for other people for specific costs. Reporting would be available for the individual and group levels. Reports could be copied/pasted, printed, emailed.