There is no ore, or even pure refined metal, so valuable that it would pay for the energy costs needed to bring it home, even if it were lying on the surface in a neat pile ready to be scooped up, at least at our present level of technology. There is one exception: if we could find some very plentiful, easily recoverable isotope there that could be converted to fusion or fission power, it MIGHT be worth our while. Provided, of course, that we had a propulsion technology capable of using it as fuel, and the fuel was not already available on earth. And if the material needed to be located, mined and refined, the calculation becomes progressively worse. We would have to haul custom specialized mining and refining factories out there, which would mean we'd need a perfect understanding of what, and where, the material was before we even started.

The cost of rare earths varies wildly by element, purity, and market conditions, ranging from hundreds to tens of thousands of dollars per kilogram, with key elements like Neodymium oxide (NdPr) fluctuating around $80-$90/kg, while high-purity Dysprosium oxide can be $280+/kg, and lighter elements like Cerium oxide or Lanthanum oxide can be in the low dollars per kilogram or $1,000s per metric ton, driven by demand for magnets (EVs, wind turbines) and influenced heavily by China's production dominance.
--That's what AI sez...

I hate to keep harping on this (although I'd be delighted if you could come up with an argument that will refute me) but this is Elon Musk space groupie talk, designed to get politicians or investors to cough up cash to finance a mission (and the contracts) to go there. Still, the scientific value of an alien technology, or even of an indigenous life form, would certainly make it worth our while, although it might take centuries to fully exploit it.

As for hollowing her out and spinning her up for artificial gravity, I couldn't tell you. I used to be able to do that kind of math, but that was 50 years ago.