Condition is definitely important, but if it works well and has 2 controllers plus a mic, that’s a good plus. I haven’t seen anyone sell a PS2 for anywhere near $144, or even $100 for that matter since before the first PS3s came out. Though @sandystrachan has a point, if you want to retain the ability to play PS2 games, PS3s these days are not backwards compatible (though I’d suggest you could get a used PS3 from when they still has this capability and perhaps user demand will bring this functionality back in future releases, and remember, if you can still buy a Colecovision and an Atari 2600 in 2009, you’ll probably always be able to buy another used PS2 system if for some reason you decide you just have to play Parappa 2 again or whatever.
What might make the most sense is, first off, if you live in a bigger city, call some pawn shops, video game stores, etc. and see what they’re selling a PS2 for, and try to undercut them slightly. People get a warranty at a 2nd hand shop, they don’t with you, so you want to knock $10 off the price you could readily get it for in your area. If you live in a rural area which doesn’t have stores where you can buy a 2nd hand gaming system, find the closest metro area that does have such stores, call a few of those stores, and what I’d do then is to take the price someone could get by going there, and maybe adding a bit to it….think maybe $5 extra for every 20 to 25 miles a person might have to travel. Whatever price you end up with, check eBay to see if it’s in line…you might want to take the 10 least expensive buy it nows you see for working PS2s, average the cost including shipping and make sure you’re at least 10 bucks under that number. You want to make sure that the price is attractive enough that both someone just passing by might think what the hey, and someone in the market for it looking for a deal would feel like he was getting a good deal. People go to garage sales to get a deal, but with something like this, there is a very active resale market, and you are going to do better by selling it outright than you would by selling it to a retailer, because they’ll pay you maybe 25% of what you could get and pocket the profit (they have to…overhead and all). Bottom line is to put yourself in the mindset of someone looking to buy, not in the mindset of someone looking to sell, and figure out hey, if I were someone looking to buy one of these, I lived around here and I’d checked into my options, what would I think was a good deal. Base your price on that. For me, that would be $50, as locally and on line you can get them for $60+.