No way is that a good deal. Is there any good bike shop or even bmx specific shop in your area? You can get a who lot of bike for around 400. Do not spend 250 on that thing though. You'd have to spend at least another 250 on it just to make it LOOK like it doesn't suck. It'll still suck even then. You don't need to spend a ton to have a pretty great bike. I'm pretty sure around 400 will get you a bike that's a bit lighter, with higher spec, and proper cranks.
Take look,
http://www.albes.com/fitprk12010stockbike-1-1-1-1.aspx Thats pretty sweet for the money though not exactly top of the line, has better parts and is a little lighter. For another 100 bucks you could get the slight higher spec str 2 and have a full chromo frame. If you really want to ride and think you're not just gonna quit in a month, go for a higher spec all chromo frame, you'll thank yourself later. I'm a bit of a snob and won't ride anything that isn't all chromo(Or just good steel as far as road bikes go).
Even if you do go used find someone who knows bmx to make sure if things are a good deal. A lot of people buy sweet bikes and then sell them as soon as they realise that riding a bike is tiring and that doing tricks is difficult. So good deals on sweet bikes can be had. That 450 dollar str 2 might be sold for 300-350 in near mint condition by little timmy who spent his communion money on it and decided it sucks. But if you're unsure about used bikes any bike in the 350-450 range at albes is a pretty safecbet. I just posted those bikes cause I think they're sweet, theres heaps of others though. Remember, if it says 100 percent chromo frame that is best!
I'm not saying you need a really amazing frame to enjoy bmx. But if you want things to be at least "good" and somewhat reliable, around 400 is where "good" tends to start.