Looking for some info and hard numbers (Boston area)

[Noreaster]

I am looking to replace my motorcycle with something more baby-seat friendly. I have driven a few different sports cars over the last month and, sadly, of all of them I have chosen the Boxster. There are two that I am looking at. Both are 2001s. One is a base and the other is an S. Neither is coming from a "Loving Home" with that nice stack of receipts in the glove box. Both seem to be all right and I wold like to take the S in for a PPI. I left a message with the Porsche dealership's service person but have not heard back from him, implying, to me, that they are not exactly burning with a passion to be inspecting a bunch of random used cars from out in the world. I guess I understand that and it does lead me to my first question:

Can any one recommend a good indy mechanic/shop north of Boston?

Which leads me directly to the second question:

How much dough should I be expecting to spend on things like Oil Changes and regular PM. Neither car has more than 45k on them. What's next and how much does it cost? I'm a little put off that the engine is so hard to get to. I am a motorcycle owner and former Land Rover Owner so doing and paying for frequent maintainence isn't a deal breaker for me necessarily, I just can't find any information on how much this stuff will COST.

And lastly, Can I put a car seat in this thing? There is no airbag disconnect switch that I can find but I suppose it might be automatic, but no light comes on any where indicating that the computer has disabled the airbag. This IS a deal-breaker, unfortunately.

I know that you guys read a million of these things! Thank you for taking the time to read this one and help out.