My budget for buying new miniatures is small compared to other hobbyists. At least, that's how it seems to me.
I've got friends who show no hesitation when a cool new game comes out. They'll purchase the starter set, including a second or third faction just so they can get a feel for the various armies/teams/warbands before deciding their favorite. Eventually, all the figures and terrain and manuals and whatever else ends up on the metaphoric 'lead pile'. God bless these early adopters! They help promote new games and maintain energy in the hobby. But, that's not me. My budget just doesn't allow for that kind of frivolity. Sometimes I wonder if I'm just being a tightwad. (BTW, I still don't have my own Flames of War army and have been borrowing armies all this time. Curses!) So, I've built up my collection by attending flea markets and by making some excellent trades.
For example, a friend posted a request for some round, plastic 40mm bases for some GW Lord of the Rings figs. I had some spares and offered them to him. He wanted to give me cash but for such a small transaction, cash just didn't make sense to me. So, I told him to trade me for some figs or bits in exchange for the bases with the caveat that he give me something he didn't need or no longer wanted. He offered me some Warmachine WarJacks and some infantry. He never played the game and the WarJacks were assembled but unpainted. We made the exchange and both sides were happy. Those WarJacks will eventually be integrated into my HotT army as behemoths.
Another opportunity came up recently. I had purchased a single French Somua-35 tank (for Flames of War) during a trip to the National WWII Museum in New Orleans. At the time, I was hoping to build an early war French army but that never happened. Another friend was in the process of building a French early year army and he offered me some of his old fantasy adventurers figs that were taking up space on his lead pile. I needed some figs for general RPG use.
So, I am now the proud owner of a gaggle of Ral Partha figs from the 80's & 90's.
I think the key to a good trade is to negotiate so that both parties feel like they are getting something good. I don't mind old or second-hand figures. Many gamers haven't had time to put paint on most of their collections anyway and I want the challenge of re-imagining something dated into something new and novel.