Even-though it's a general purpose website builder, Wix offers enough tools to build a full Music Studio admin solution.
It has a forever free plan that comes with ads to their service. For $4.50 you can connect your own domain and for $9 you get booking, payments, invoicing, calendar synchronization and more.
Website address example: username.wixsite.com/sitename (you can see why you'd want to connect your own domain)
With Wix you also get access to their ever growing apps marketplace, which you can use to enhance your site as you please (apps can be free or paid)
On the Cons side, the fact that it's not tailored specifically for Music Teachers can make Wix a bit difficult to use for beginners.
Conclusion: Wix gives you all the tools you'll need for your Music Studio and more. The main advantage is that you can start with the forever free plan and pay for functionality as you need it.