How often for an alignment?

[mylamb]

Thanks for all the responses because I have often wondered this as well. I have another question related to alignments.

Can you go to an alignment shop & give them the proper alignment specs for your Boxster & expect to get it done properly or do you HAVE to go to a dealer/specialist & pay $400 - $500 for a laser alignment? Dealers are telling me that they are the only ones who can properly align the car. My tire shop is well known for setting up autocross & track vehicles & they say they charge about $70. I'm sure it's "slightly different" from what a dealership is doing but seriously... is a dealership alignment worth 7X's the price??? I can't imagine it is.