On your booking, click the Actions menu button
Then select the Hide Pricing for This Client option.
This option is only available on Clients in Confirmed Bookings - it is not available for Proposals.
Note that if you share the link at the bottom of a Proposal to someone who is not intended to see the pricing, that person will be able to see the pricing regardless of whether or not pricing is disabled for that client, because they are not required to log in to see everything in the Proposal from the proposal link:
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