MS-1 is a moored rig, anchored. they have been selling recently...

MS-1 is a moored rig, anchored. they have been selling recently for $50-80M, when new she was around $280M.

The DP3, Dynamically positioned drill-ships, or DP semi subs (Valaris, DPS-1 that Woodside is presently using) at the height of the market before the 2016 (drilling industry) crash were costing $700M, but that's for twin derick, dual BOP, rated to water depths greater than 12,000 feet (higher formation pressure / temperature).

Though when the crash hit, drill rig day rates were smashed, $700k/day to $120k/day, else rigs were cold stacked and lots of tonnage was scrapped as many had no work for 4-5 years, some great tonnage was scrapped.

The biggest drilling companies all went chapter 11, done have re-emerged. New builds that were ordered, prior to 2016, some companies paid a few progress payments on them, then walked away as couldn't get finance, as banks knew the market rates had plummeted.. shipyards in S.Korea and Singapore were left with stranded assets. Some of these assets, not commissioned, or completed have been sold for huge discounts, $40M to $120M, compared to original build order rates.

The MS-1 used to be the Atwood Osprey, it's only a 6th generation unit, nothing complicated or high spec. But a day rate for a rig is only part of the story, as lots of other associated costs, supply vessels, 3rd party contractors, labour hire, choppers, drilling consumables, list goes on and on. But big pictures it's not that much as a part of the planning cycle.