Used SD3

How much should I pay for a used sd3 and what issues should I look for when I pick it up?

I was hopeing to get started for about 400, and I see it is fairly upgrade friendly ?

Or for my first unit should I pick something else?

Thank you for your opinions.

400 seems to be a good price, take care of the head(see it works).

it's a good choice for a first unit