I think you're better off to just fit it on one GPU, because when you move to multi GPU, you have data that's moving between them, the training becomes more complicated, it's easier to make mistakes, and it can be slower in some ways. Also, on one GPU, you can use unsloth, which gives you a 2x speed up. So that's quite beneficial if you can just focus on keeping things simple, until you've at least got a training approach that's working well, and you're happy to then spend the time and money to scale up.