Required features - web dashboard, inbox to which I can forward invoices (with scanning abilities), trend charts, breakdowns, report export. *Not* required - employees expenses tracking.
We use inDinero for company expense tracking. It hooks into our bank account and automates all the P&L reporting. They also have accountants that help with end of month clean up and at tax time!
I track all of my payments received, expenses (including payments to contractors), and taxes for my small business through this product and it's been invaluable.