Coinbase may allow you to pay with some reversible payment methods, such as via a debit card that result in you having to wait a shorter wait time until you can withdraw the purchased coin to your trezor.
See below:
In general, debit card purchases or wired funds from your bank to your Coinbase USD wallet do not affect your availability to cash out—if no restrictions exist on your account, you can use these methods to purchase crypto to send off of Coinbase immediately.
Some of these payment methods may result in you paying a higher price, or a higher fee.
OP, if you want to save fees, then look in to using Coinbase Pro rather than just plain old Coinbase. It requires you to learn how to place market orders, but it means your trading fee will be 0.5% or less (depending on volume), rather than up to 2.49% or even more (depending on payment method and size of purchase).