As has been said, eBay can be hit or miss, which as far as buying a first vintage may not be ideal. Most BIN prices are too high IMO.
I've had a few misses, and quite a few good hits on eBay, but I now know what to bid, and the details to watch out for.
(I had quite a few misses in the beginning)
It's easy to get carried away with bids, and actually pay over the odds for something that might not be as good as you'd like.
Second thing that has been mentioned, redtips, and a few others vintage are quite in demand, mint ones are not that readily available and command high prices.
(some which are just not worth it.) Just compare prices of Slims & Fatboys on eBay and on here, you'll be surprised by the difference.
Send me or Steve (Sunburryboy93) a PM, and I'm sure we can find you something to get you started for a decent price.
Both Steve and I are collectors, we do this for the fun & passion of it, not as a money making venture. (we both still have a day job!)
Max