ancam

I want to create an appointment for a specific client at a specific pre agreed time so they can then click on it and pay for it and, most importantly, agree to my terms. How do I do this? I've blocked out the time in my scheduling calendars so no one can book me during this time but can't seem to offer an appointment for that one client unless I open up all my room resources at which point someone else could book my time in the meantime. Is there a way to do this? Would creating an order enable them to click on terms and agree or not? I've never used orders before and can't find any info on them on the docs? Thank you