I have a yellow P5 with 20% all around and paid around $160 in 2002 or 2003. Had it done in HI soon after purchased. I believe 35% is legal there on the front driver and passenger and anything goes on the remaining windows. I believe CA is no tinting on front driver and passenger and anything on the remaining windows. I could be wrong though. I did receive one fix-it ticket in CA for the too dark tinting on the front windows equaling about $100. I was pulled over specifically for the tinting, but I suspect the officer was hoping for something to add on to that, but there wasn't. I paid the fine and left the tinting intact. I'll consider it a tax for the privilege of having a uniform dark tint.
also, HI annual safety requirements include checking for light transmissivity of tints. I don't think CA has a similar requirement in their smog checks - just the highly accurate eyeballs of the police.