NFT smart contract where NFTs keep being added over time. Does every addition necessarily cost gas?

Question

The title sums it up. I was thinking of doing a erc721 contract where I'd keep adding overtime, instead of all at once. The question is, every time I add an NFT to the contract, I'd have to pay gas, this being on Ethereum. Is there any way where I could post the contract and keep adding NFTs to it post contract submission, without paying gas?

Answer 1

The EVM allows contract state changes (eg writing the new token owner and metadata to the contract storage) only as a result of a transaction.

And to answer your question - yes, transactions always require gas to be mined.