Costs
The creation fee, the trading fee, and gas.
Launching
A creation fee of 0.0004 ETH, plus gas. That is the whole of it: the position is token-only, so there is no liquidity to fund, and anything sent beyond the fee is refunded in the same transaction. The owner can move the fee up to 0.05 ETH and no further. The wallet shows the exact gas before you sign.
Trading
The pool's 1% fee on the input of each swap, plus gas. The launcher charges nothing on top, and collecting or claiming fees costs only the gas of the call — which anyone can pay, for any token, on anyone's behalf.
Why launches are cheap
Three decisions. Tokens are EIP-1167 clones of one implementation, so a launch writes a 45-byte proxy instead of deploying an ERC20. The description and icon are emitted in the Launched event, where bytes cost 8 to 16 gas each, instead of stored, where a 32-byte slot costs 20,000. And the launch ticks are constants rather than computed on chain, because every launch opens at the same price with the same range — see The pool.