It depends on the vehicle. There's development costs (which can be substantial). There's manufacturing costs. There's fixed recurring operational costs (which

It depends on the vehicle. There's development costs (which can be substantial). There's manufacturing costs. There's fixed recurring operational costs (which get averaged over the flight rate). There's incremental operational costs. And then way down in the noise is the fuel cost. For most rockets manufacturing and fixed recurring operational costs are the biggies. There's only so small you can shrink a production line and an operations team, and there's only so high you can push your flight rate, the combination dictates your per flight costs to a substantial degree. For a vehicle like the Shuttle which was quasi-reusable the fixed recurring operations costs were dominant. It cost several billion dollars a year just to maintain the standing army of engineers and technicians plus the facilities needed to keep the Shuttle operating. And because the Shuttle's couldn't fly more than once or twice a year per orbiter due to the long processing time between flights that resulted in a very high per flight cost even though manufacturing and fuel costs were low.