Vorker turns site measures into fixed quotes, books the snag list and raises the final invoice for fitting firms of 1-5 people. You approve everything it sends.

No. Every quote, invoice, email and text is prepared and then waits for you. You can read it, edit any line, reject it, or approve it and schedule it to go out later. Nothing sensitive happens on its own.
Two-person firms get the most out of it, because there is nobody else to hand the paperwork to. Vorker is built for businesses of one to ten people, not for large outfits with an office team.
It drafts from your own rates and how you quoted similar installs before, and it gets closer the more you use it. Treat the first draft as a starting point you adjust. That is still much faster than building every fixed quote from scratch.
Vorker reads the confirmation emails. If a date moves, it flags it and drafts the message to the customer with a proposed new plan. You read it, change it if you want, and nothing is sent until you approve.
You photograph the snags on the walkthrough. Vorker lists them, books the return visit in your calendar and drafts the note to the customer with the list and the date, held for your approval.
No. You talk to Vorker the way you would text someone in the office, and it works inside the tools you already have: your email, your calendar, your accounting. The quotes and invoices arrive as ordinary PDFs.