I agree. Try and find someone that already has the gear and give it a go first. I love the buggy and use a Peter Lynn mk2. They are a great buggy that you can adjust to suit you and with the new options from PL, the adjustments are endless. There are so many types of buggies out there so try and find one that suits you best. The main area I fly is only about 150m long so I have gone for a small buggy that I can do some freestyle with, but can also be used to get some decent speed when I hit big open beaches.
As for price, I dont know what the second hand market is like in the US, but here in Australia you can generally pick up second hand buggies for less that AUS$500 (about US$450).
I hope that Helps.