Welcome to Shopify Community. My name is Olivia and I work here.
Thanks for your question. We provide detailed documentation around transferring your business safely and thoroughly that you can check out in this doc. You'll notice we outline the following disclaimer to be taken into consideration while you explore selling your business:
In case you're not familiar with Shopify's Exchange Marketplace, it's a service we offer to help you connect with buyers and securely transact the sale of your Shopify store. Part of why we emphasize this disclaimer is we are otherwise unable to protect your information during an external sale.
I highly recommend that you move the sale over to our Exchange Marketplace, but if for some reason you are unable to, then I invite you to connect directly with our Support team for additional assistance. Make sure to reference this forum thread when you reach out for faster support.