When you still have not solved problem with pending bookings which still block the time slots so we need to make people to book in advance so please add new features with Cusotmers Groups addon with Deposit Payments addon (and other cashless payments). IF Some addon for payment installed -> DO NOT SHOW "payment at place (store)".
Deposit Payments addon improvement requirement to set on bookings in few days later.
These days I just now I require from blacklisted to pay by coupon and they get email about it but paid bookings by coupon get new status from pending to approved manually. But I do not like when some black listed cliend block the time slots even they are on pending status.
Black listed clients should NOT know they are on black list because they would start to use fake user details in booking appointments.
We still do not have Deposit Payments addon but if you will have this mentioned so we will definetelly buy it.