So, there are a lot of different ships on the sirius market.
There are Shipyards producing them.
Now, what about this:
Each shippclass has a limited amount of produced ships in-game at it's sale locations.
Each of the selling location can hold a number of the ship(s) it sells.
If a player buys one of those, there will be one less availible on the station for <time>.
Example:
-Liberty Gunboat at Norfolk shipyard:
5 are availible each <time period> (i.e.: month)
Player1 buys one of them.
4 are availible until the amount of ships of this class availible will reset.
Now, in numbers.
There should be more fighter class availible than bombers.
More bombers than Gunboats .And so on.
As a fixpoint I would say, there should be only 1 BS availible, 2 cruisers, 3 Gbs for an period of time. If that/these is/are sold out, you can't buy one.
Maybe the period of time the availability gets reset should be longer as bigger the class of the ship is.
That would definetely limit the amount of caps out there.
It would make the ship trade forum more important.