Great question — answering as the UphillTech team:
This is pro feature and your best bet would be to contact Dokan support. Or just go trough the module and see what options you have. From what i see in the docs quotes are saved in database so there are few options to make it but i would just investigate best approach trough the code. https://dokan.co/docs/wordpress/modules/dokan-request-for-quotation-module/
Full answer by Snuffy: https://stackoverflow.stackexchange.com/a/79932470 (CC BY-SA 4.0).
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