Scanning makes a 3-D record of someone's building, so it's good practice (and in some places the law) to ask first. Preflight keeps each answer with the exact wording the customer saw.
Two ways to ask
On the phone: tap Scan Rooms on a customer with no answer on file and the permission screen comes up. Hand over the phone: the customer reads it, types their name and signs. Customer Said No records that you'll measure by hand. You can also tap Sign on This Phone with the customer's measurements.
By link:Send Permission Link (app) or Get a permission link to send (web) makes a page the customer can read and agree to. When you book an estimate visit with an invitation to the customer, the link is added to the email automatically.
The customer's screen then shows Permission to scan on file — name, date (or that they said no).
Customer isn't there
On the permission screen, Customer Isn't Here — Scan Now lets you scan right away when the customer isn't on site, or when you're just practicing. Pick Get Permission Later or Just Practicing / Testing. Nothing is signed or saved as permission: the customer page keeps showing No permission to scan on file yet, so send the permission link before you use the scans or photos for that customer.
Settings
Company Profile → Permission to Scan: turn asking on or off, and use your own wording (type [company] for your name). The standard statement covers what's captured (3-D scan, photos, video), why, who sees it, that you don't sell it, that they can say no and still get an estimate, and that they can ask you to delete it. If you share data for research, it says so.