CondoButlr alternatives

I'm currently testing because I need a booking program for my 12 seminars with 10 - 15 participants so far and maybe later also for online appointments. I managed very quickly to understand the system and to make bookings that worked. A standalone program that works without your own website and it can also be linked to your own website. That's exactly what I needed. Since I understood it so quickly and intuitively and the customer service has been very reliable so far + great clarity, I give it 5 stars. I will write supplements later when I have more experience.