I've recorded a bunch of songs which are ultimately going to require a proper drummer. I don't play or have a studio so it's going to require setting up remotely. What portable machine would I need to run big sur and the latest GB?

I'm sure any of the current MacBooks could handle recording live drums (with a suitable interface/mics/etc), so it's just a matter of balancing cost vs future-proofing. If you think you might eventually do more high-end recording work then a MacBook Pro would probably be the best choice. There are models that use the new M1 chip (with an option for an Intel CPU), as well as (more expensive) models with Intel i7 & i9 chips. If you go for an M1 model, be sure to do your due diligence re compatibility of any 3rd-party software you use (including interface drivers). Whatever model you choose, I'd bump up to 16GB RAM, and an internal SSD of 1TB (512GB bare minimum). If you decide to save a little $$$ and go for a used/refurbed older Mac, be sure to check OS compatibility -- I got one from OWC, but there are plenty of sources, including Apple's own refurbs..

Thanks. I definitely need to save money since I doubt there's going to be many mp3 sales for punk songs about yeast infections.