Just for reference, I bought a brand new CD32 on eBay about 18 to 24 months ago for $49.00 plus shipping. That estimated price of $400 is ridiculous!
The new ones from China were always just over $100 with shipping, but they didn't include an SX-1 ($100-$200?) or an FMV module ($250+?) I think $400 is fair.
$70 or so for a used CD32 is also quite fair, especially considering new ones don't seem to be available anymore.