When the build is complete, select the project under Projects to expand it, then select Transfer to Homeowner (it's there for projects you created). Choose whether to email the transfer or share a private link or QR code, enter the homeowner's email (their name and a message are optional), check the preview, and select Send Transfer (or Create Link). The whole project transfers — there's nothing to pick and choose.
The homeowner signs in to Homvio — or creates a free account — with that email address to accept it. Once they do, the home and everything you documented move to their account, and your access to the project ends.