My ignition sometimes does that too... I'm not sure why, but I haven't researched it much.

The key almost needs to be in an exact spot 1 of every 200 starts.

Definitely make them fix it before you buy it, and see if you can get something else thrown in... because I just got my 05 black manual for 11K with 36,000 miles (And have seen people getting even better deals than that)