The final Ethereum transaction fee required to set up a Safe depends on a number of parameters:
Number of owners.
Usage of the ProxyFactory.
Additional logic set (e.g. FallbackHandler).
The following numbers assume that you create a Safe via our web interface at https://app.safe.global/
A Safe with 2 owners requires about 263k gas.
A Safe with 3 owners requires about 309k gas.
A Safe with 4 owners requires about 331k gas.
The following calculates the transaction fee with a number of example gas prices:
An interactive calculator by @germartinez can be found here. Another one by @cryptoneur_eth is located here.