Hello!...
any example to apply some pattern to divide logic and data structures of a contract type erc721?

I have a contract that I am building that is at the limit, (a marketplace with auction)... I would like to have 3 contracts, one for the logic of the marketplace, another for the auction, and the main one on top of these...
question, I've been researching but I don't understand which is the best way to do it.
Whether to use library, or to make 3 contracts and import the 2 in the main one and instantiate them....

Which would be the best way?

Thanks!