Hi jamito, thanks.
Yep, my conversion was an estimate. Way too many zeroes and millions in rupiah... I may have paid twice but at the end of the day I paid max US$20 (just under IDR 185 000) for a drive from Kuta to uluwatu and back, plus a tip for the waiting time. Was good enough for me, so didn't quibble the difference.
I paid all the tolls and parking as far as I am aware. Peanuts, so again didn't quibble.