Get it in writing, without the writing
Quotes accepted in the portal and work signed off with a decision trail: dated, attributed, and impossible to lose in a thread.

On the record, by default
Accepted in the portal, not in an email
The client reads the quote where their projects are, and accepting it is a recorded event with a name and a time, not a reply saying "yep".
Days, hours, items and fixed sums
Discovery by the day, an audit by the hour, licences per item and go-live cover as a fixed sum, on one quote. The budget burns down against the lines with a day equivalent.
A decision trail instead of a paper trail
Milestones go to the client for sign-off with an optional note. Approve or request changes: either way it's on the record, and an approved billing milestone can be invoiced.
The decision sits on the work
A task sent for sign-off shows as with the client until they decide, then as approved, with their name against it. Nobody has to go looking for the email.
The client portal →