Do chapters have unrated ships?

[Inquisitor_Lensoven]

Destroyer, frigate, cruiser, etc are what would be considered rated ships of a fleet, do the various chapters utilize unrated vessels of war, or would that be considered too much flexibility for it to be safe for space marines to (traditionally) have?

[Karhedron]

It's a big galaxy and the Inquisition can't be looking everywhere at once. As long as Chapters are fighting the foes of the Emperor and submitting their geneseed tithes, they are usually allowed to get on with the job without too much interference. Many Chapters are thousands of years old and may have vessels on their fleets that do not conform to current classifications. It is is not unknown for some Chapters to custom build wargear although whole starships seems a bit of a stretch.