Starship question

From what we've seen in the Rogue Trader rulebooks, the parts within a ship are pretty variable. Someships come with parts that can not be removed (like the Dominator class cruiser and its additional flight decks), but a lot of other parts can be swapped out (life support, engines, weapon arrays, additional armor, ect.)

Certain vessels ARE STC. We know that Astartes strike cruisers and battle barges tend to be STCs.

Many others are not. Just like many things in WH40K, it mostly depends on the precise situation.

What Vaz was getting at...

There's no real universal currency in the Imperium of Man. And due to the vagaries of the Warp (both for travel and communication), market prices are hardly universal. Something disgustingly common in one portion of the Imperium might be all but unheard of in another. Not only is currency not stable, but the items themselves are also mercurial in price.

In short, no idea. There's simply not enough lore out there to determine it.