You generally do well with Ebay as long as you're careful. Always check the sellers feedback from other buyers. If there is anything you are leery of, find another seller.
I bought my FIPK and Predator Tuner on eBAY. The (brand new in box) FIPK was more than $50 cheaper than the online retail price, and the (used) Predator tuner was >$200 less than a new one.
Oh and by the way -- I'm 41, married with only one kid. We both make good money and I put money aside for mods and "toys". Of course if push comes to shove, family needs and house expenses come first, but that's not usually an issue.
2003 Black 10th Anniversary Cobra
#353 of 10th Anniversary Editions. Born June 9, 2003
BBK CAI, Magnaflow Catback, MGW Shifter, M/T Drag Radials