Margin per client, computed from hours already logged
You find out the project lost money after it ships. Every hour your team logs updates that project's margin, per client, with no spreadsheet and no second purchase. Cost rate per hour is returned only to Owner and Admin, so members and clients never see internal cost rates, and billable capacity is measured against weekdays rather than calendar days. So what: you catch the overrun in week two, not at invoice time. Honest limit: the numbers come from hours already logged. There is no forecasting and no margin alerting.