Base 2013 M3s can be leased right now for sick ass cheap
$500/mo $0 down if euro delivery
$600/mo $0 down for US delivery
It'd be almost foolish to buy instead of lease a new m3 right now unless you're deadset on keeping it for years and years and years, considering that the F32 M3 will be out in a couple of years. Lease the e92 for 3 years, then decide if you want to buy it out or get the F32. Leasing gives you that option, plus its a no brainer lease at this price.