Unfortunately, transaction fees (Payment Fees) cannot be passed on to clients at the moment although this is something that we're considering as a feature.
For now, the workaround is to raise the service prices on your proposals.
If passing on payment transaction fees is not allowed in your jurisdiction, it is important to avoid having a line item/service called merchant fees, transaction fees, payment fees, etc being charged to the client.
We highly recommend that you confirm the legality of this transaction in your jurisdiction. Your jurisdictions may have controls in place for these fees within their Consumer Protection Laws (CPL).
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