A deposit takes part of the price when the client books. It is money in your account today, it reduces the sting of a no-show to something survivable, and it filters out the least committed bookings before they reach your calendar. The cost is friction: some clients will not put money down with somebody they have not met.
Card-on-file takes no money at booking. It holds a payment method so that, if your terms allow it, a late cancellation or a no-show can be charged afterwards. Less friction at the point of booking, but you are collecting after the fact, which is always harder than collecting before it — and the client has to have agreed clearly to the terms for it to be defensible.
The practical split most professionals land on: deposits for long, expensive or hard-to-refill services, and nothing at all for a thirty-minute appointment where a gap costs you very little. Charging a deposit on everything to solve a problem you only have on Saturdays is a good way to lose midweek bookings.
Whichever you use, the money is yours and moves through your own payment setup. Friday Scheduling is not in that flow — we hold the schedule and the terms, you hold the money and the relationship with the client.
Start with new clients only if you are nervous about it. A deposit for people you have never met, nothing for your regulars, is the least disruptive version of this and it catches most of the risk.