lex400sc

Just bought my SC4 not too long ago and now it needs it's 45k service. I've never had a Lexus serviced before so I am clueless as to the costs. What kind of damage we're talking here in $$$? I just need an average ballpark or even your own personal cost. I figured most SCx00 owners here should have reached the 45k threshold by now, so if you could just give me a run down so I know how much money to transfer into my checking account. Also I noticed that my cats pop a lot after I shut off the engine, could this be because one of the exhaust pipes are brand new? And sometimes when I'm accelerating, I can hear and it feels like something in my tranny is grinding. If I let off, the sound goes away, but it never fails to show up next time. Suppose all this stuff needs fixing/tuning, how much am I looking at? I also think it's worth mentioning that it's getting serviced in California, SF no less. Thanks for all your input.