I have used the same driver for years, and he was recommended to me by a friend who still uses him.
Would highly recommend him, great knowledge of English, and has a new Avanza which is very well maintained.
Happy to share his contact details if anyone wants to PM me.
For a full day tour - I normally pay 800 000 if its Kintimani or Amed type of distance, plus his meal, and a tip at the end of the day.
A private car tour for less than $80 USD pretty good value in my opinion.
There has been a suggestion just to find a driver , but some of these do not have insurance or drivers licenses, so a personal recommendation is always worthwhile