[Perfectlap]

my advice: try to get one that still has some warranty left. Before the warranty runs out go to warrantydirect.com and invest in an extended warranty, some think its a waste but for a one time fee of $1500-$2K I say what the hell. Make sure you have full service records. Have it checked out by your local Porsche dealer from top to bottom so you can find any problems before the warranty quits.
Check to see if your state has lemon laws like here in New Jersey where dealers are mandated to cover the powertrain for six months from the date of purchase.
It might be worth a trip down here.

Look for a Boxster low low miles, GOOD PAINT, the options you want like HID lights(aka Litronics), wheels etc. THese items are expensive to add later and you don't want to pay for them new if you don't have to.