Whats a DD 3510D worth?

ok, so i'm looking at a sub from a local guy to stick behind the seat of my single cab truck. One of my friends has a 3510D for sale, its used, he ran about 600w rms on it in a sq setup. I have no clue what new is on dd subs since they are not published on DD site, but he said he forked about 450 for it, and is asking 200. Good price or pass it up? I have seen pretty nice expensive stuff go fairly cheap on this forum and not sure how abundant or low these things go for used.

thats a good price...

ok cool, too bad cause he told me if i got it like with in the next two days i could have it for 175, but gotta wait till i get paid again Hopefully i can get it and get at least a 145 out of that 1 10", that would be sweet!

i dont see how you couldn't get a 45 out of one 10 in a single cab, if i can do a 46 with 4 from a trunk surely you can do that number.

well i'm going to attempt it with low power at first, then up the juice. I have always just built one box and ran with it, with no box adjusting or tuning.. Loudest i ever got 1 sub was the 1 12" sub setup in my sig, and that was a pioneer 12" in 3 cubes with 71 sq inch port. yea i agree a 145 is not that hard for anyone with the right amount of power, but i want a 45 with lower power first to prove a design.