Have pity on a newbie. Just tell me which ones to buy, and I'll buy them instead. You can live vicariously through my purchases...!
I'm forced to take a sabbatical. I grabbed an antique gold filled Waterman Ideal, circa 1910, for my father. After snagging something like that, I need to ride the high for as long as possible.
As for cheaper Watermans on eBay, you can get Allures that aren't labeled in the description for between $20-30 easily. With some more searching, you can even get a Waterman Agora (similarly unmarked) in the same price range. Both models are from the 80s/90s and are no longer being made, but they write like butter.