I mean I do a couple outcalls a month...and all my incalls are cash only, no bank transfer or giftcard under any circumstances. Had no issues so far. I find most guys prefer it that way as its discreet.
I started taking deposits 10 years ago due to unreliability of new clients and sometimes clients who'd seen me once, twice, even some regulars. I was fed up of the chopping, changing, no shows, not bothering to confirm, confirming late. New clients were blocking my diary for regulars who were reliable. I'd tried everything suggested, I stopped accepting new clients because for other reasons I had regulars wanting chance to see me before a planned move and change to outcall only. A new client who really wanted to see me said he would be prepared to pay a deposit. I won't work without a deposit now, and learned has to be first 2 bookings because (just as when i didn't take a deposit, 50 % would let me down on the second booking).
When it became possible to offer a limited number of incalls I carried on taking deposits,
I still have some new and repeat client reliability issues even when the deposit is relatively high, but I'm not in a 'high traffic area'. Clients usually have to plan to travel to me, or me to them.