Customers often know exactly where they want the head table or the bar, and it's quicker for them to drag it there than to describe it. Customers can move tables and chairs lets them do that on their event layout, with one rule: the customer decides where, you decide what. They can move furniture. They can't add, remove, resize or turn anything, and nothing they do changes what's booked.
Turn it on
In the layout editor's Customer tab, switch on Customers can move tables and chairs. It's off unless you turn it on, layout by layout.
The customer needs to see the layout somewhere: their quote page (Show on the quote), their customer portal (Show on the quote, or Show in the customer portal on a job you booked without a quote), or the share link. Move tables and chairs appears in all three.
What they can move
What never moves: tents, generators, lighting, restrooms, hand-wash stations, items drawn as Other, drawn areas, text and reference marks, and anything you locked with Lock. Lock any piece of furniture that has to stay where it is before you turn this on.
What the customer does
Start over puts their drags back so they can try again, and Cancel leaves without saving. Once it's saved they see "Thanks! Your changes are saved and we've been told."
Everything has to stay on the drawing. If the layout was changed while they had it open, their save is refused ("This layout was just updated. Reload to see the latest version, then move things again."), the page reloads by itself, and they see the newer version before moving anything again.
What you see
Their change is saved to the layout straight away; there's nothing to accept.
If you have the layout open in the editor, your next save there is refused and the editor asks you to Reload, so nobody overwrites anyone; reload to see their change on the drawing. Changes by the customer picks up a new change within a minute.
Put a change back
Put back beside a change returns their items to where they were. It only moves the items that are still where the customer left them, so anything you've moved since stays put. It's an ordinary edit in the editor, so Undo brings their version back if you change your mind. The change then reads "put back by" with your name.
Check the plan afterward
A customer can drag a table into a tent's stake zone, or closer to the next table than your spacing guide. Nothing stops them, because those are planning guides, not rules. Open the Check tab after a customer change to see any warnings.
Moves and approval
Where things sit is part of what the customer approves. If the layout was approved, a customer's change makes it Changed since approval, and their page asks them to approve the new version; the message they see after saving says so. See Customer Approval.