Apologies if I wasn't clear. When I said the "extreme case" I meant some kind of future scenario where rocket launches operate similarly to commercial aircraft flights (doing launching and landing to fixed infrastructure, minimal refurbishment and operations between flights, hundreds of launches per core, etc). So, the '99%' savings wasn't intended to be anything approximating where we are now, but more like the limits of the possible cost savings if everything else is nearly perfect.
As I mentioned, I think _today_ SpaceX is saving about 30% per launch by doing reusability (which, in my mind translates to ~20M). So I actually think we're probably in good agreement.
I estimate those costs would be $20-25MM; still, a big savings on a brand-new rocket each time!