The five bay sibling to the DS923+, same Ryzen R1600 platform and ECC support with one more drive slot and a second expansion option. The extra bay matters more than it sounds for RAID layouts, since five drives in RAID 6 gives you three drives of usable capacity instead of two.
Across 3 listings tracked in the last three days, the median total cost in USD including shipping is $840, and the lowest is $600. RackSniper flags a listing once it falls at or below 70 percent of the trailing 30 day median, which for this product means roughly $588 or less. Condition and configuration vary widely on used enterprise hardware, so treat the median as a reference point rather than a target.