It would be great if the option "billed by prject hours" could be combined with a "fee cap" option, which is very often used with law firms. This would allow to show all time entries on the invoice (which could accumulate to let's say 20k US Dollars (and therefore showing the client how much work has been done), while still only invoicing the fee cap of let's say 10k US Dollars. Alternatively, it could be realized by allowing to show "time entries" on the invoice for "fixed fee" projects.