Comment on page
section, display the list of quotes that have been submitted and can view details, edit, delete for each submission.
With quote submission popup view you can edit the price and quantity of the product. Especially if the store owner agrees with the quote, he can convert the quote to draft order. Then he can easily add tax, shipping or discount code and send the invoice.
In case the product is priced at 0 by the store owner, when converting to draft order, the store owner needs to add a custom item with the price and quantity agreed with the customer.
And then send the invoice
The store owner can print the quote to a PDF file regardless of the state of the quote. In addition to product information, printed content may also include a message (annotation) of the store owner.