I have a similar method as well.

To add, I would use verify him or similar blacklist sites. However in this day and age some desperate dommes will abuse blacklisting sites in an attempt to keep the client to themselves. So it may be a moot to use this method. But If they provide a reference it kinda helps.

I personally make my clients fill out my form and force them to provide a form of ID with a selfie. My form makes it easy for them to provide a deposit in conjunction. Then there is light communication until the day of the appointment reminding them of what to expect. I find forms to be an interesting way to weed incompetent or problematic clients. There will be idiots who will default to writing essays in my inbox and when I direct them to my form its crickets.

The problematic newbie is a scary scenario, I wouldn't be surprised if they get their deranged ideas from social media. Sorry to hear about your scary experience.
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