Chuck Street in Los Angeles.
Chuck is based at Fullerton (near Anaheim).
Commander Chuck.
I paid about $100 per hour for JetRanger time, but that was a few years ago.
The rate's probably gone up but he's open to negotation depending upon how many hours you do. I did 5 hours a day for 5 days: 6-9 am and 3-5 pm. You fly all over LA, South to Orange County and North to Malibu.
It's mainly straight & level which is of limited value, but Chuck will adapt to what you want to do. We did a few confined area, pinnacle, and roof-top helipad landings each day.
There's another place at Van Nuys. I can't remember the name now but I'm sure someone will post it.
I'm only a PPL and was doing it for fun. I think it's probably of very limited value if you're building hours to be a professional pilot. Lots of cheap hours in your logbook, but are you really building useful experience?