I have a smart contract for selling Painting in crowdsale, Once the Painting is sold in crowdsale the owner of the painting can trade it to other user once the crowdsale is over. I have to implement a buy function where the buyer can buy the painting only if the seller has interest to sell it.The problem I am facing is that How can a buyer know whether the seller is interested and at what cost is he comfortable to sell? Once solution I have thought is that to make the function multisig where both buyer and seller need to sign to transfer the painting and accept the Payment.
Ps :- How to implement multisig feature to a function to sign
setPrice
(callable by the seller) andbuy
(callable by the buyer)?setPrice(2**256-1)
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