OK. Thanks.
I'm surprised, maybe just anyone (especially local Bluebird Taxis) would be interested in an 8 hour, 16 hour round trip fare. I was thinking there would be a "long haul/transfer" desk that would focus on those distances.
Now to figure out the price.
The local hotel is charging IDR 1,200,000.
Last time I was in CGK, a daytime taxi ride to my hotel was IDR 125,000 with tolls, and the hotel nighttime discount was IDR 200,000 (30% off).
So, maybe that could be a starting point.
Thanks.