An internal quote process app is a brief before it is a screen. Name the file that is the system of record today, who may change the price, and which PDF the buyer actually received. If those three answers live in a folder name, the first release has a job.
What release one stores
The record carries the account, the lines, quantity, unit price, discount, the margin you are willing to show internally, a status and the file that went out. Mail can stay as evidence. It does not remain the place where the agreed total lives.
Leave the price engine for later
Release one copies the columns sales fill by hand this week. A rule you cannot write down does not enter the build. Campaign trees, a second currency and a full archive migration are later decisions. HED Creative writes that boundary in discovery, from Berlin or Ankara.
If one office prices and another approves, say so in the brief. The screen then shows the editor and the approver on the same record. A shared inbox is not a role.
The PDF stays on the record
The file the buyer receives is generated from the current record. The number read on the phone and the number on the PDF come from the same place. A later edit creates a new line on that quote, with a name and a time.
What you still run elsewhere
Accounting and the ERP stay where they are. The app ends the week in which three people defend three totals. Old folders stay in the archive until you name a year worth moving.
Ask for the scope on web app development. The choice of which sheet goes first sits in which spreadsheet deserves a first release. If the same owner should keep the app after launch, talk to a software partner.